Guess it's time I chimed in to keep the ball rolling. I won't try to put these in any sort of order until I reach 50 and even then it will be difficult.

Let's start off with two on which I concur with Senor Doyle. Clark Terry - In Orbit (1958), Gil Evans - Out of the Cool (1960).

For the remaining eight in this list: Eric Dolphy - Live at the Five Spot, Volume 2 (1961) (only two tracks but brilliant nonetheless), Lester Young - The Jazz Giants (1956), Hanky Mobley - Soul Station (1960) (as noted by Joe Goldberg in the liner notes "you simply hear four men swinging lightly, powerfully, and with great assurance and authority"), John Lewis & Sacha Distel - Afternoon in Paris (1956), Donald Byrd & Doug Watkins - The Transition Sessions (2CD - 1955-56), Steve Lacy - Work (2002) (pushing 70 and two years before he would pass on but still showing the youngsters that compromise is always a dirty word), JJ Johnson - Proof Positive (1964), and Lennie Tristano - The New Tristano (1962) (Track #2 - "Requiem" one of my fave piano jazz tracks period).