I'm sure everyone already has nice collections of components, but it might be nice to share what we've got. I've tagged things with [cheap] if money is no object, i.e. I don't care and I'll trade you a pack of gum or something for whatever you want.
[$3/ea] AD620AR DIP instrumentation op-amps
[cheap] resistor and cap indexes in 0805 and 0603
[cheap] a lot of thru-hole passives including a resistor index and a ceramic cap index and most other common components
[cheap] RGB, IR and other thru-hole LEDs, SMD LEDs in many colors (0805 or 0603, I can't remember), 7-seg displays
[cheap] misc switches
[cheap] Dupont connector bodies, male+female pins (VERY HANDY!)