Just think of all the things you can do with your new “wall.” You can paint a mural on it, push a desk up against it, or even project a movie onto it. Just don't assume that your roommates won't hear you having sex behind it.
IKEA hack! Attach 4 Ikvar side units with piano hinges.
Get the directions here.
Source: ikeahackers.net
Build a divider wall.
A bit complicated, but if you've got the handy skills, this is a very professional look that gives you extra wall space to place seating against.
Source: bhg.com
Use Billy bookcases from IKEA.
Watch the tutorial.
Source: youtube.com