The Bulbcap is (you know it's coming) a bright idea. It's a little rubber sheath you put over an unsightly bare lightbulb to turn it into a slightly more sightly, slightly less bare bulb. It comes in colors, and can safely be used on bulbs up to 40 watts. (I'm studiously avoiding going for the easy joke here...I just want you to know that.)
The Bulbcap is a simple but elegant concept. I wonder, however, how big the market for this product is, since I don't have many bare bulbs in my house and neither do any of my friends. But it's something I'd expect to see selling well at IKEA, so subconsciously I must think there are a lot of people who need these.
I assume Bulbcaps are pretty cheap, but the only sites I can find them listed on aren't in English, so I can't swear to it. Also not sure what U.S. availability is.
Follow Up: These are carried in the U.S. by Friend, who say they only have a few left and they cost about $18.