If you've got a slightly rusty but perfectly functional bike hanging out in your shed, good news: There's someone out there who wants to display it in his loft. Favored types include early BMX models (manufactured between 1965 and 1980), Raleigh and penny-farthings. If the bike is in good condition and appeals to a collector, it can be worth between $200 and $500. A surprising warning: "Please don't restore the bike before you sell it," says Patrick van der Vorst, founder of ValueMyStuff.com. "Collectors of bicycles want to restore them themselves; hence, any restoration you would do might actually take away from the value of the piece."