LETTUCE is (a) the prime ingredient in a salad, (b) a slang for cash, (c) a green herb that can be smoked, (d) a genre-busting six-member funk/jazz/soul/jam/psychedelic/hip-hop/art-rock/ambient/ avant-garde/experimental collective formed in 1992 by four alumni of the prestigious Berklee College Of Music, or (e) all of the above.