I am familiar with all of Kex's list and give a hearty second to it. Probably throw in Monk's Criss Cross and Mingus' Mingus Ah Um. I can't say enough about the Alison Kraus discs. Even if you don't like bluegrass/country/twangwhatever check out New Favorite---breathtaking.

I'd reassert my support for any of the Martin Pearlman/Boston Baroque series as well...

Thanks Slosh and Dusty for suggesting some more modern fare. I'll be sure to pull the trigger.