Really really hard choice.
1. Pearl Jam - Black
2. Pink Floyd - Any Colour You Like (or Us and Them; can't choose.)
3. Mastodon - Capillarian Crest
4. Buckethead - Padmasana
5. Buckethead - Sketches of Spain (For Miles)
Others that switch into the list at random times are: Buckethead - Lurker at the Threshold Part 2, Too Many Humans, Earth Heals Herself, Soothsayer, Final Wars, Baseball Furies; Bob Dylan - Mr. Tambourine Man, All Along the Watchtower, Tangled Up in Blue; Foo Fighters - Best of You, The Pretender, Everlong (Acoustic); The Mountain Goats - No Children (Moral Orel woot!); Pearl Jam - Alive, Garden, Once, Porch, basically all of Ten; Pink Floyd - All of Dark Side of the Moon, Dogs, Comfortably Numb, Run Like Hell, Shine on you crazy diamond, etc. Lots of Pink Floyd.
A little more than 5. Oh well.