Hal Cragin was a bass player for Mono Puff. You can hear some of his work on The Hal Cragin Years. Some people think he held the band together.
From http://members.tripod.com/~fark/bass.html :
Hal Cragin's work for Mono Puff (and They Might Be Giants) is also one the most amazing pieces ever put together. His addition to their songs is something right out of classic 70's funk. Truly a show-stopper.
He played for TMBG on Factory Showroom (he co-wrote S-E-X-X-Y too) and Severe Tire Damage.