I discovered the play/pause hotkey (space — great choice, by the way — can’t believe Windows Media Player doesn’t support this!) by accident as I tabbed onto the "Register" button and attempted to trigger it with my spacebar.

Edit: Baaa! I found your nano-easter egg. :)

Took me a sec but ? is the same as pressing shift+/

Anyway you can get that to work nicely with Firefox's find-as-you-type feature?