Whatever you decide, can you paint the firebox a dark color? I think that will go a long way in making it look more real.

I've seen several non-functional fireplaces with an arrangement of pillar candles. I think it's a clever way of still having that fireplace glow without needing a log or a working fireplace. You could also try putting a pretty statue, urn, or art piece. Anything that reflects who you are usually will look great in your space! I am partial to the pillar candles, though. :)

Please, no wine rack. What about a couple vases interspersed with candles? You could change the vases to reflect seasonal items (pumpkins in the fall, ornaments in the winter, etc).

I kind of like it white - maybe a picture of the rest of your room to find a good theme?

If it were my faux-fireplace I would use a sense of humor here. Add something that shouldn't go in a fireplace, like a ceramic animal from Jonathan Adler (http://www.jonathanadler.com/menagerie/)!

i do like the idea of candles... or put in a log holder and logs...you don't ever have to light 'em up!

Here are a few suggestions:
1. completely fill it with decorative logs like so: http://2.bp.blogspot.com/_2Imdx9tBDI0/TD2hCOS2jgI/AAAAAAAAGbE/hpFAe7oznZo/s1600/apartment+therapy.jpg
2. If you have a cat, put the kitty litter in there behind a screen.
3. Multiple candles like your house mate suggested look great.
4. Put statues or ornaments in it.
5. Put indoor plants in it.
6. Put vases with flowers in it.
7. Fishtank?
8. Install bookshelves.

You'll have to remember that the heat from those candles will have to go somewhere if its a fake fireplace. I had wanted to do the same thing with mine. Instead I now have my mouse cage hiding behind the screen. If you wanted to put a wine rack down there then yeah, you could use a screen to disguise it. Personally I like it for storage if you can't use the candles. Let's face it, apartments are usually small. What waste the space?

I have a nonfunctioning mantel, so I hung shelves in it, one has vintage faux fireplace logs and the other has books, The irony never escapes and always sparks conversation, no pun intended.

please don't put a wine rack in there. after a quick online search, i found this blog post with a few classier-looking options: http://little-inspirations.blogspot.com/2010/06/fireplace-fillers.html

Here's an article with several ideas-the mirror one is cool:

http://www.realsimple.com/home-organizing/decorating/fireplace-decorating-00000000033391/index.html

I also like the look of stacked books:

http://supamb.com/supafine/2009/08/11/storing-books-in-our-fireplace/

http://storyofadot.wordpress.com/2009/10/16/fire-place/

Or potted plants:

http://www.southernliving.com/home-garden/solutions/built-in-solution-both-sides-fireplace-00400000007670/

And white fireplaces look really great filled with stacked wood:

http://www.designscouting.com/2007/11/07/inspiration-wood-fire-place/

I would paint the back a dark color and leave it bare. It will add depth to your room. Not every space needs to have something in it. Sometimes empty spaces can be more interesting.

I was considering moving into a place with a decorative fireplace and thought about getting a Gel Fireplace. They come in lots of different sizes and use those gel fuel canisters. I was even thinking about a DIY project of it.

Stuff a turtle in it: http://nibsblog.files.wordpress.com/2008/05/opt-turtle-shell-fireplace.jpg

No, I'm kidding! Here are some related posts from AT.

http://www.apartmenttherapy.com/dc/ideas-for-putting-your-nonworking-fireplace-to-work-095374

http://www.apartmenttherapy.com/chicago/heat-cold/decorating-a-nonworking-fireplace-044653

http://www.apartmenttherapy.com/dc/living-room/outfitting-the-area-around-your-fireplace-inspiration-gallery--131408

http://comfortandluxury.blogspot.com/2010/03/off-season-fireplace-fillers.html

http://www.realsimple.com/home-organizing/decorating/fireplace-decorating-00000000033391/page2.html

I've seen a fireplace where they used section of french drain—terra cotta, and stacked it inside the fireplace and somehow lit it from behind and each drain pipe section held a bottle of wine and it looked pretty amazing. But just sticking a wine rack in there is not going to look good.

I was going to say the books idea as well. If you want to go the candles option but do not want real fire you could get some wax battery candles (Target has them) that look realish. They would work well here I think. Put in some big tall lanterns could make a nice area.

toy firetruck...

stack of logs, all nicely cut, with fairy lights draped through them

it's a fantastic changing niche, take it in turns to play with it.

Mirror in the back of the niche and candles in front. A nice, cosy glow.

You could combine your ideas! We have a ton of candles in varying sizes behind a screen in ours.

i've had houses with both functioning and non-functioning wood fireplaces. all were either painted black inside, or black from soot. the black was like a big black hole that sucked in light. I took a stretched canvas and painted it pewter with metallic paint and put it against the back of the firebox. the canvas reflected a bit of light and could be removed to use the fireplace.

I put framed artwork in my non-functional fireplace. Two pieces just casually lean against the wall. For me its a great way to casually incorporate artwork.

I love this look from A Cup of Jo:

http://joannagoddard.blogspot.com/search/label/joanna%20goddard%20house%20tour

We have a non-functional fireplace and we have a candle piece it in (Not sure the name of it, but I googled 'Candle screen').

Ours was much cheaper and from BBB, but it looks something like this: http://www.bellacor.com/productdetail/475502.htm

completely fill it with firewood, ends facing out (this might mean they need to be halved)

why not both? put the candles behind a cool fireplace screen. Screen is moveable when you want the candles, right?

I would stuff the open space with wood. I saw a picture once of a non-working fireplace that was nicely stacked with wood. It looked amazing.

I'd fill it with logs, preferably cedar for the fresh smell. Just like this...

http://pinterest.com/pin/1627288/

when i had one, i wanted to get a bookshelf that would fit inside of it and fill the space with books. but i never got around to it...

The toy fire truck idea gave me a good chuckle!

If you're allowed to paint I'd be tempted to paint the inside of the fireplace black and then use lots of pillar candles to try to replicate a fire.

My mum's friend has a similar fireplace in her dining room, and she did something I thought was genius - she cut sheets of copper to line the inside of the fireplace, and then put an arrangement of pillar candles in there. The copper reflects the light and looks gorgeous.

That might not look great with your current white paint, but it's a thought!

i agree with bekkapalmer about having a sense of humor about this.

i have a nonfunctioning fireplace. my roommate and i put an old metal tonka truck and a playboy puzzle from the 1960s in the space.

candles or a wine rack are so overdone and uninspired. please don't waste the space in this way.

+1 for stacks of wood... you could glue or screw them together like we did. We're hiding a subwoofer behind ours as well! Nifty! Check out this picture of the stacking type we used:
http://www.flickr.com/photos/timo/4254622365/

I have a functional fireplace but one we don't use often. I put a framed photo of a log fire in it. It's gotten a lot of good coments from visitors!

I had a non-functional fireplace in one apartment that I put a small water fountain in (and a few small plants). It gave it a garden grotto vibe.

Painting the background black as many have suggested makes for a very dark room. Our nonfunctional fireplace is currently painted black b/c it came that way when we bought the house and I've yet to repaint. I have candles in our fireplace and I don't think the dark background adds to its ambiance. I really like the stacked wood.

Fill it with books!

https://picasaweb.google.com/lh/photo/r0z4bJkyOJHEYy3sIbhWyw?feat=directlink

If it were my fireplace I would put a mirror in the no fire area and put some candles as well!!

What's everyone's problem with the wine rack? I thought it was a fine idea.