Active Surplus sells a great bunch of spare parts, weird knickknacks, and supplies that are hard to get elsewhere. Plexiglass cubes, anyone? It's good for cables, especially, and some kinds of electronics--mostly hobbyist stuff. The computer stuff tends to be from the bronze age (mid 1990s), and the selection varies. But the WTF Award goes to the box of spare plastic doll arms.
I also get a kick out of the junk-shop ethic. It's a shame that the famously incongruous fake gorilla no longer stands outside (they keep him at the top of the stairs now). But there are nice touches: the tray full of digital clock displays has a sign that says, "Get a digital display so that when you oversleep for school you can blame it on your crappy homemade alarm clock."