[This was described and named by a coworker who doesn't post to this site. I told him to visit, but doubt he ever will. If he does, I'll gladly delete this post, but it's too great not to share.]
My coworker had a very small flat but very tall ceilings. So he and his roommates bought inflatable furniture and filled it with helium instead of air. Then if some friends come over for the evening, they can reach up and grab what they need, but it gets out of the way when not in use.
Unfortunately, the particular furniture they had was armchair form and rather durable, so the helium *just* managed to make it float. You could put it up at the cieling, but it would slowly sink. A piece made of thinner material, or one with lower surface-to-volume ratio such as a sofa, would actually have positive buoyancy.-- michaeltherobot, Apr 22 2006 Halfbakery: Zero-G furniture Zero-G_20furnitureTo rent for a party, not as a permanent space saver. [jutta, Apr 23 2006] Oh, puleeze, not helium furniture again!-- DrCurry, Apr 23 2006 Could you not just have normally inflated furniture attached to the ceiling with an elastic cord or one of those pull out washing lines. In fact it wouldn't even have to be inflatable furniture, plastic garden chairs and table would be fine.
Disadvantage: you have to use the chair underneath the cord.
Advantage: Helium chairs might float to cover a light and burst.-- marklar, Apr 25 2006 I'd prefer lightweight furniture with easy-to-attach pulleys. But the idea itself is cool.-- phundug, Apr 25 2006 random, halfbakery