Tim Curry, John Ritter, Annette O'Toole, Richard Thomas, Tim Reid, Harry Anderson, etc.
When appearing on Saturday Night Live (1975) in 1982, he performed a "geek trick" by sticking a long needle through the skin of his forearm. He said to some squeamish audience members "It's just a trick!" Then to show that it wasn't "real," he moved the needle back and forth and blood began to pour out of the "wound".
harryanderson @ 1 month ago