Coolest? Steve Albini (only because Bill Hicks is dead).
Prolific musician (Big Black, Rapeman, Shellac) and engineeer/producer (Pixies, Jesus Lizard, Killdozer, Helmet, Fugazi, Nirvana, Pegboy, OM, Dirty Three etc..etc) of some of the best music of the last 20 years.
Big Black...