The famous LaChoy Dragon.
I've been meaning to post these for a few weeks now, but just hadn't gotten around to it until now...the famous LaChoy Dragon commercial Jim Henson made in the 1960s (Frank Oz is in the guy in the dragon suit).
And if that's not enough vintage Muppet commercial fun for you, check out some Skip and Scoop spots for Wilson's Meats from 1966.
Links via Nate Pacheco's blog.
30/03/06 Update: One more classic Muppet commercial, a Wilkin and Wontkins spot from 1957.
10/04/06 Update: Several of these links were pulled after Nate got a cease-and-decist letter from the Jim Henson Company. Not surprising, but it's a shame since there's clearly a demand for this kind of vintage Henson material and it's not otherwise available.
