By converting your Schwinn to a single speed, you'll almost definitely increase its resale value, at least for the time being. People are paying out the nose for fixed gear and single speed bikes on Craigslist, just check out our Craigslist thread, or the bikesnob blog, or your local Craigslist.

I know personally that thrift store/garage sale bikes I used to sell on Craigslist for $50 two years ago, get $150 now, and these aren't even converted yet! So I think you'll do well to convert it, even if I personally feel that a good bike should be left alone.