I saw him in the first SS Live show I went to, Big Bird & The ABC's, back in 1994 (imagine that later in the 90's LOL). I remember him being VERY energetic in the show, in fact, I think he even literally jumped off the stage at one point.
I found it funny at one point when he is doing 'Hip to Be Square' with Bert and the others, he was wearing shades haha.
Don't forget him singing his line in Cookie's 'C is for Cookie' number 'C Is For Cucumber!'