It's gents like guitarist Nels Cline that can make you realize how little you've done with your life. he has played in more varied contexts and with more heavyweight players than you've had hot breakfasts this year (maybe ever) and shows no sign of resting on his well-deserved laurels. Emerging in Los Angeles' free improvisation scene in 1978, Cline has since plied his protean, feverish electric six-strings with jazz great Julius Hemphill, Bay Area improv wizard Henry Kaiser, rootsy noise-rockers Geraldine Fibbers, mutant fusioners brother Alex Cline and Scott Amendola (another local lad), Mike Watt, and he's now even a regular member of Wilco. Apart from Mothership Wilco, Cline has a "power trio," the (instrumental) Nels Cline Singers, and his most recent opus is the double-disc Dirty Baby, a conceptual collaboration among Cline (leading a large group), poet David Breskin, and L.A. artist Ed Ruscha. When does he sleep?