His role in The Dirty Dozen was one of my favorite characters too.
Rick, I don't know about all those film credits after RED, whether they were in theatres or just for TV. I just knew about the one small character part he had in RED.
He's done a whole bunch of voiceovers as Mermaidman on the SpongeBob cartoon. I know the kids recognize his voice but have no clue who he is/was, and the older generations were probably unaware of his work on the cartoon.
Here's a cool interview I found where he talks about Mermaidman:
http://www.youtube.com/watch?v=AsHhZ_bnpQg