It's funny how you can labor under a delusion for years and years before you're set straight. I had a Sesame Street record as a kid -- The Stars Come Out On Sesame Street -- and in my memory, the best song was Oscar the Grouch and Johnny Cash doing "Five Feet High and Rising.' Well, thanks to Ugly Floral Blouse, I now know that it was Biff, not Oscar, and Mr. Cash. After a little digging around, I found that Oscar and Cash did duet, but it was on "Nasty Dan." That song was also on that record; I'm going to try and dig it up now too.

Johnny Cash -- Five Feet High and Rising
Johnny Cash & Biff -- Five Feet High and Rising (via Ugly Floral Blouse)
Johnny Cash -- Wo Ist Zu Hause, Mama? (in German!)