Funnyman Robin Williams was once accused of stealing fellow comedian DAVID BRENNER's jokes. The Good Will Hunting star was once threatened by Brenner in the 1970s after he believed Williams was using his material, reports gossip column Page Six. Brenner phoned Williams' agent and screamed down the line, 'Tell Robin if he ever takes one more line from me, I'll rip his leg off and shove it up his ass.' Recalling the encounter in a new book Comedy At The Edge, Williams explained he was simply "sampling" material from others.