This is so good, I have to mention it. I noted a post titled “The Complete Norman Granz Jazz Sessions” on the blog rhapsody rock school. The description was interesting, so I gave it a play.
One word describes this: WOW!
Basically, it's a bunch of prominent 1950's-era jazz dudes jamming their brains out, all nicely recorded and beautifully mastered. This is a 5-disc boxed set with 18 tracks. Do the math — it's actually 4 tracks per CD for the first four CDs with two tracks on the final CD. The shortest track is 11:55, the longest is 27:20. Yikes.
If you have Rhapsody, just do a title search for “Complete Jam Sessions”. You'll find it. And if you have any sort of interest in jazz, you'll be lost for hours.