http://reddit.com/r/loadingicon and similar places list interesting (if not especially useful/practical) concept art ostensibly useful as loading graphics.

Is there somewhere I can similarly find good small sound effects useful as startup chimes? I'm only aware of the Mac and Indy boot sounds, which obviously surface due to their reputation as being used at boot time. Surely there are other cool sound effects, I'm just not sure where to look for them.