geeze, a picture of what you have would really help...

Do you think you could paint it? Or you could turn it into a shelf of sorts, buy a piece of wood to place on top of it and use it as a decorative place for books, plants, photos, a lamp, etc. You can also buy enclosures for radiators...for example, try http://www.beautifulradiators.com/
Also, try placing a few antiques around the apartment to help blend it in to the decor so that it doesn't stand out like an eyesore.

If you can't hide it, flaunt it. Paint it bright pink or something, maybe paint it the same color as the wall, then paint a few stripes on the wall in complimentary colors outlining the fracking thing. I have one of those as well, I just painted it high gloss optic white.

As erinmotley says, enclosures are great, and with some paint can either almost fade from view or become a real feature. Just don't put a plant that doesn't like dry heat on top of one. And if you have a cat, be prepared for him to claim it, the same way they like to cuddle on warm computer equipment.

A shelf just above it will work, especially if you put items on it that echo the lines of the radiator.

As for painting, I once saw a radiator painted in a metallic brass tone. It might have looked tacky, but instead it perfectly echoed a fireplace screen and chandelier.

Make a "window seat" on top.

Try to paint it, i did the same thing - just yesterday:) -and it turned out pretty good... but first i tried to get rid off the old paint as much as possible, and then a aplied a white bright polar white...i think this is the first step, and later when you start decorating the place you can put a shelf and put books or plants on it...good luck!

I have large radiators in almost every room in my home including the bathrooms. The good thing is mine all have a lot of great detail and scroll work in them so they look cool. They do take up space, but I think they add charm and character to each room. I wouldn't try to hide them or make them stand out. Just leave them as is and they become part of the aesthetic. In summer time, they are a great place to prop a vintage fan to create cool breezes throughout the house.

http://www.woodenradiatorcabinet.com/

Ooops - I hit submit too soon!

WRC made a few cabinets for us several years back and the finished products were wonderful. Maybe the landlord will pay or split the cost? If you're going to be there a while, it may be worth spending the money.

Why not turn it into a console table, like this Ikea hack? http://ikeahacker.blogspot.com/2007/07/radiator-cover-up.html

Mount a shelf above it and a panel to cover it up (if you don't have the two side pillars, you can add sides to the panel) and make it into a nice console table area.

If you can't DIY a cover, BostonWood on Comm Ave. out past BU does good custom radiator covers, and they can add shelves on the sides or above to make it more like a bookcase. They have a terrible website but are actually great!

I love Pi's idea!

...and I've harbored a not-so-secret love of radiators and radiant heat since I was little. In my first apartment, my radiator in my bedroom was hidden from door and window view, so I used the top to (I can't believe I'm posting this!) dry my delicates. You know that fresh-from-the-dryer feeling? Imagine a warm bra on a frigid Minnesota morning. It's one of the best feelings in the world.

We have all our rads painted bright colours, highly contrasting the wall colours. It's such a great heat source, & looks awesome in our post-war (WWII for us Canadians) bungalow.

I find rad covers so tacky...

I agree with @MackeyBlue, I also have radiators in every room of my apartment and while at first I was scared they might be seen as an eyesore, now they just add the aesthetic of my home.

I found an oak quilt frame that just fit around my radiator with one of the crossbars about six inches above the top of the radiator. We hung hooked clothespins from the crossbars and then were able to hang mittens, scarves, etc to dry out.

Now that the kids have grown, I will have the radiator enclosed.

whatever you do, remember that it's a radiator, and needs to be properly vented so that it can radiate heat in the winter.

All of our rooms have radiator enclosures. As noted above, they must have proper ventilation. We use them for plants, objects, and in the bedrooms as window seats.

Radiator covers are a fairly easy DIY:

http://www.thisoldhouse.com/toh/how-to/intro/0,,1582598,00.html

Here's a blog I follow where the author painted her radiator bright orange. Just thought you might like an example of what a painted radiator can do for a room...

http://brickcitylove.com/2010/03/01/secret-project-revealed/

I am in the process of building a few radiator covers. They aren't that hard and you only need a few tools. Miter cuts for the molding are probably the hardest. The plans I got are from This Old House.

What about putting a vintage fire screen in front of it? Or a short three panel metal screen. That way, you can take it with you when you move, or sell it in a tag sale.

ooh, I'm having the same struggle with mine! mine is "new" but cheapy - so nothing really cool or salvageable about it. I rent, and I cannot paint it. luckily I don't use it (never had the gas hooked up), so no need to vent. Mine isn't a wall unit - it takes up a lot of space.

i'm inspired by all the ideas for turning it into a console! thanks. :)

I don't mind the look of an exposed radiator. In fact, that orange radiator looks awesome. This is sort of along the lines of the people who write in wanting to know how to disguise their pillars.

On the other hand, I'm a sucker for a great IKEA hack...

The Bookcase Factory Outlet on Galen Street (Newton, near Watertown Sq. ) also makes really nice enclosures for radiators - ones that are part bookcase. They are really nice to work with, and made the covers for my radiators.
www.bookcasefactoryoutlet.com/

thanks guys i appreciate the suggestions, im thinking of painting it white and putting some plants on top and art around it!

paint it traditional black and add a shelf size of marble on top.

Painting a radiator a bright colour is a great idea and I love all the examples I’ve seen.

What about this kind of radiator though?
http://houselooks.net/wp-content/uploads/2009/09/slimline-radiator.jpg

I see that the large, old school kind (like the orange one linked above) looks fantastic clad in bright paint, but would a bright bash of colour work for this flatter (but equally bogstandard) variant? I hate our white radiator on our landing, because although it sits quietly enough against white walls, it still mars our otherwise cosy, light reading nook/landing strip.

I have the exact same scenario in my condo. I thoought of a simple radiator cover, but I didnt want to break up the wall with an awkward box right in the center of the wall. Instead, I created a window box bench. I used simple 3/4 in plywood and built a box that goes from wall to wall with a metal grate to let the heat escape ($85 in materials). It looks great. The radiator is hidden and as a bonus I have a new seating area and plenty of storage on either side of the radiator. I used this as the model. you can create one that is removeable or fixed to the wall.
http://www.lowescreativeideas.com/Libraries/0707%20Project%20Images/0707%20-%20WW%20-%20WWI%20-%20Hero%20-%20Sit%20and%20Stow.sflb

My company BattyBuilt specializes in designing and building custom radiator covers to suit any style, any room. We serve Westchester NY, Manhattan and Connecticut.

Here is a link to the website: www.battybuilt.com

If your looking for the highest quality of work as well customer service, my company BattyBuilt specializes in designing and fabricating custom radiator covers. We serve Westchester NY, Manhattan and Connecticut

Heres a link: www.battybuilt.com

for something a little different see www.couturecases.co.uk.

Many options to choose from, you can design your own or create something very personal. All very lightweight or easily dismountable so if you move its easy to take with you