I made a really simple shade for my window like yours. I only hemmed the sides. (you could use a hemming tape if you don't sew) Then I hot glued the top and the bottom to a very thin piece of wood trim, screwed the top wood inside the top of the window pain, then used two ribbons to tie it up. hmmm doesn't seem as simple as it was when i write it out.

I like the mono chrome of this bathroom. If you feel you need color, I like yellow folded shades, nothing too obtrusive.

Window Decal Stickers! :)
Get a swirly pattern in yellow or green or purple and it'll look lovely. OR multi coloured spots would look great too. :)

My sister's bathroom is very similar to that. We did the black and white with a slate\grey-blue color.. a muted grey-purple shade would probably work very well also.. for the window, i made a roman shade out of a woven white-on-white stripe, then used the same type of fabric in black to make a small box-pleat valance similar to this, but only about 6-8" long. the color on her wall went all the way down, though, so the white stood out more than it might on yours. could stick with the black\white there, and bring the wall color into towels and such, or bring more color on the window also, perhaps by using a darker version of the wall color or the valance.. or if you want even more color, a very pale color or other material for the shade as well. very pale yellows would look great with a grey-purple... or doing a shade with a sheer fabric would also be nice.. let you keep light coming in while the shade is down. the bridal\dress section of fabric stores have ones with little metallic sparklie bits that would be fun! okay.. enough rambling now, i'm sure you get the idea.

Either a deep eggplant colour (fabric), or go with a light wood tone shade like birch slats or bamboo.

I had the same dilemma and our bathrooms aren't terribly different. I did a roman shade out of mini-blinds. No sewing required and they look good! The directions came from Little Green Notebook. Here's a pic of my bathroom: http://14cali.blogspot.com/2010/03/major-catch-up-part-1-bathroom.html

I also really like the monochromatic appearance you have going on - so I wouldn't introduce a color at all but stick w/ Grey or White curtains instead.

I think it looks really classic as it is. Keep the window treatment style in line with the shower curtain or, as suggested above, a simple Roman Shade in white. I'd suggest you bring color in with your accessories or towels, things that can easily be updated without really disrupting the elegance of the existing color palette.

Yellow and grey toile on a white background for window covering. Plus maybe some yellow accents? Yellow soap? Toothbrush holder?

I think white so it blends in with the wall, not a block of color. As said above bring color in with other items.

A ribbon roman shade like this one from Pottery Barn:

http://www.ecrater.com/product.php?pid=6431536

Some of the crafty folks over at seaglasslovers.ning.com are doing fun window hangings with glass found on the beach. Here's a look at one I made for my bathroom window. I don't like curtains but need privacy and wanted something to take up the expanse of the window glass.
http://seaglasslovers.ning.com/photo/2517530:Photo:106552?context=user

Maybe shutters or a shade? Look at this web site for ideas: http://www.smithandnoble.com You can browse the photo gallery there by room to see some suggestions and maybe even come up with your own low-cost way of replicating a look.

I'm thinking wide paneled shutters painted a bright color could look really nice.

Wow, this is really black and white! I am thinking that unless you do a highly saturated color, it's just going to go "blah". So, stick to the extreme: Hot pink!

I would do a hot pink roman shade, accented with some grosgrain ribbon in grey and black. I would leave it be the only shot of color in the room, or else it will look very "coordinated" and fussy.

Another option would be a gray, white and black print. Geometric in a 30's deco way or a soft toile.

It's so funny... if this had been posted as an "After," there'd be all kinds of advice (and cries for) color. ANYway...

If you only add color to the window (I'd do an inside mount Roman shade) it might not look complete. I'd consider a small piece of art, or your shower curtain, or even a bar of colored soap as other ways to integrate a color scheme fully. Otherwise, a curtain alone will look a bit like an afterthought.

But kudos for understanding that even a wood blind is-- and will add-- color. With your current palette, you don't need "pops of orange" or a crazy Marimekko-Anthropolgie-Urban Outfitters-Etsy shower curtain to get some color in there.

It's not a very attractive window, I'd go with a dark painted grey (gloss) slatted shutter *or* a translucent roller shade, something with some texture.

As an aside, I'd move the curtain rod up a bit to be even with the top of the window frame (if possible) the outer shower curtain looks heavy so close to the floor. I think the shower curtain is a bit bland, some fun, bold black/white or grey/white patterned fabric (I'm sure somebody could run up a shower curtain someplace) and the matching window shade would pull it together. Good luck!

http://windowfilmworld.com/stained_glass_window_film.htm

Some kind of roman shade would work best IF you feel like you need window treatments but it looks like frosted/textured glass so it's more aesthetics than function. You could also bring the line of your shower curtain up to be even with the window and treat them in the same fabric (it doesn't have to be plastic!). You could consider keeping them the same length which would be a different look for a bath, but interesting, and even carry the curtains all the way across the wall. If you do that, keep them subdued but not plain. A nice textured weave would work.

But if it were mine, I wouldn't add anything to the window. I like the clean lines, especially in a small space. What it sounds like you might really be thinking is "how can I add some style to this room?" It doesn't have to be through color. You could do a graphic wall decal in b&w or a silver-gray which would add a ton of interest. Or find a really interesting mirror. Or even drop a mini-chandelier in the middle. It could benefit from a "pop" of drama even more than a pop of color. Good luck!

muted purple or a grayed blue... If you've seen Behr's Rhino, a shade like that would be gorgeous.

I agree with previous comments, either a roman shade or shutters would be beautiful in your bathroom.

I think you either need to add more pops of color if you decide to go with a colorful window treatment, like small, maybe just a couple hand towels on that shelf or a small picture, a candle, maybe even a different rug... or just stick with black and white. It might look weird if you only have one colorful object with all of that gray.

If you decide to add some color though, i've always been a fan of yellow and gray together... super classy and super mellow. :)

thanks, please keep the comments coming! So far I'm definitely leaning toward roman shades. somewhat similar to what lindsayae77 suggests in her post & link! no clue what color fabric but I do think it needs to have some gray or white in it so as not to provide TOO much color in that one spot.
I also plan to put some paintings on the wall above toilet and on an empty space when you first come in to the left. those will help w/ adding a little color as well.

whats your favorite color?

My suggestion is to go with either true orange, turquoise blue, pink/magenta.

I, too, like keeping the bathroom monochromatic, which allows you to have have different color towels or accents you can easily rotate. (I regret renovating my bathroom with blue floor tile instead of something neutral. I have quickly grown tired of it. But I digress.)

I think painting the molding around your window would add interest... a silver gray (even metallic) and use a nice white shutter. Then, add an ornate antique silver framed mirror on another wall, if you have room, to tie it together.
To my mind, this would look elegant!

favorite color = green. various shades. definitely a no go in this room. lol it's a part of almost every other room in the house though in some form or fashion. :-)

Try a window shade with a Marimekko-type of print that contains hints of grey or black. I think that splash of abstract color would be lovely.

I also have a grey/white bathroom and i used an orange sari as my window treatment. i also added floral rugs with that have the colors: orange, black, and white. But I think any bright color would be a great contrast.

MARIMEKKO

Love the floor. If you bring in color, make sure you echo the color somewhere else in the room as well. One window shade isn't really going to cut it, and will look out of place in an otherwise monochromatic room. Try matching it with a cool bathmat. Or find some accessories (soap dish, etc) to coordinate.

i think a simple straight valance would be nice in either a plum or yellow-gold. personally, i wouldn't go crazy with ribooned roman shades or wood blinds - the contrast in material and style would seem way too off in my opinion. nice bathroom by the way!!

What about the enje in light blue?

http://www.ikea.com/us/en/catalog/products/20192159

FUSCHIA!

I would do something with the window if you decided to put color elsewhere. I'm partial to vertical stripes and monochromatic color schemes. Your bathroom is exactly like my bathroom. I made my shower curtain from thick and thin stripes of black, white and turquoise. The window curtain is a sheer turq edged in black. the rug and towels are turq, too.

This might not be your thing. But, in my old place I wanted something to obscure the view in the bathroom window yet still let light in. I also didn't want a heavy fabric treatment. I found a stain-glass encased in a wood frame and hung it in the window. That way, I got the light in and some colour and it obscured the view as well. Good luck!

Let the window curtain match the shower curtain. Attach ribbon or trim to their hems using double-sided tape. I'd like something that echoed the trim on your towels! Change to new colors as your whimsy takes you, or for each season.

I'm stealing an idea from another AT post:

http://www.apartmenttherapy.com/uimages/la/lahotposts040410.jpg

Check out the top left hand corner. I think something like this would work for you, because I can't imagine more fabric in your narrow bathroom (plus I like, detest fabric in a bathroom and try to use it sparingly). Just a thought, and sorry if this was posted already!

I should clarify -- a film, or a flat panel would help achieve this look. You may even be able to fit a tension rod in your window frame and change out a sheer panel.

What’s the name of the color you used on your walls? Thanks!

I have the same bathroom and love what you've done with it! It looks awesome. Where is the organizer from? I've been looking for something very similar... I love how narrow it is.

Thanks so much!

gray and yellow fabric, like a print, that way it blends with the rest of the room