One of the saddest part about apartment living is that many times you can't paint or add the personal touches that you would want to if it was your own home. Well, I recently was watching the Nate Berkus show where he talked about adding fabric to a wall with liquid starch! You can frame it, line a wall, or whatever your creativity dreams up and it comes off easily with a damp cloth when you want to remove it (which Nate also mentions is a great idea for decorating an apartment)
Here is the idea from his show and obviously you could use any pattern of fabric that would work for your style. The possibilities are endless!
Here are a few more project ideas...
These I found through another great blog Just Flew The Coop where she describes how to do this and remove it.