Reader Ville Väisänen sent word of a free sample library, made with the Korg Monotribe:
I made this free drum/percussion sample pack with my monotribe. I found it is great box for such sounds; with pitch and filter envelopes and great sounding resonant filter I recorded some pretty powerful analog bass drums, effect sounds and other percussion.
There are 90 files available for download as 24bit wav files, above or via SoundCloud. They are CC licensed.