I would like to start this thread with a cover of a classic bass line by James Jamerson - Motown bassist - Jackson 5 Darling Dear. The guy who is covering it is doing a really nice job of staying in the groove and getting a decent tone. Jamerson played with one finger and called it "the hook". I'm working on this one because the rhythms are so funky, give it a try - not as easy as it might sound.
http://www.youtube.com/watch?v=ebzgMV58wME&feature=related