I know you are but what am I?

Question: What kids' show promised in its opening theme, "A nuttier establishment you've never seen"?

The secret word is: laugh

Talking furniture, marrying fruit salad, a creepy floating magic head...yeah, I'd say the theme song was probably right. Pee Wee's Playhouse was a definite Saturday morning ritual at my house when I was younger. My friends and I would make up a secret word of the day and we'd scream whenever anyone said it. And that was in high school and college, long after the show had been taken off the air. I guess some things just stay with you as you age.

I still say "I know you are but what am I?" in my best Pee Wee voice. I even sometimes bust out a "Meka leka hi, meka hiney ho" when necessary (is it ever really necessary?). I'm not sure I understand the appeal of a nerdy guy in an ill-fitting suit talking in a grating voice and screaming a lot, but it sure did work for me for some reason. And what a launching pad it became for some careers! Laurence Fishburne as Cowboy Curtis, S. Epatha Merkerson as Reba the mail lady, and Phil Hartman was a writer and played Captain Carl. What a cast!

No wonder the show was good for a laugh! AAAAAAAAAAAAHHHHHHHHHH!

Answer: Pee Wee's Playhouse