This has been brought up tonite by AB and at the same time, listening to Jim S.'s discs also suggests to me that it is a discussion ripe for the having.
AB asked things like, are you supposed to try to stump people? Are cuts from a Mosaic set too obvious? Does it have to be jazz, what about "cool instrumental music"?
In the meantime, Jim has included stuff that I wouldn't have considered at all.
So, #1, I'd like to suggest that we agree to stick to jazz, in its many countless forms and not stray into other genres. It is a jazz board, even as we talk about other musical forms with almost as much enthusiasm.
#2, as to AB's questions, I would say that the point is NOT to stump people or to find the most obscure recordings. Pick tunes you like by artists you admire. Don't go looking for obscurities, but don't avoid them either. Give a mix. Make it a tune that will be recognized by an artist you might not expect. Find a middle ground-not too easy and not too hard.
Music from Mosaic sets are fine-Dr. J. used one himself. Any source is fine, too-CD, LP, private recording even. I used a track from a VHS tape.
As people are getting their own compilations lined up, I think it would be a good idea to hash out opinions on these matters, especially for people who missed the earlier discussions of these issues.