 He has collaborated with or shared the bill with, Charles Mingus, Peter “P.D.Q.Bach” Schickele, Allen Ginsberg, Ed Sanders & The Fugs, Robert Bly, Bob Holman, David Amram, Marilyn Crispell, Andrei Codrescu, Artie Traum and Happy Traum, Jay Ungar, Molly Mason, Phil Donahue, Amy Goodman, Natalie Merchant, Kate Pierson (B-52s), Raoul Vezina, and Ron Whiteurs, among many others.Through the years, Horowitz's stage style and content has been compared to Lenny Bruce, Lord Buckley, and sometimes, mistakenly, to Brother Theodore.