Shaun Usher at Letters of Note posted a collection of letters from Muppets. Actually, the letters are from Caroll Spinney (who does Big Bird), Jim Henson, and the Swedish Chef (penned by Henson).
Also included is a series of complaint letters about Sesame Street's character The Count. Link
Ho Komissionooster Sjolund!
Sveern hund der meenskroo skort herg dah smorgasbord bord bord.
Gloo das click click ein mein filmikin den Washington fom des Fancy Food, goôde des griting zoo des Kükenmenenstoof.
Yay boo thanken svenson eet des goo goo Per Nilsson und des Eilest Nassell fer yoom yoom.
Bork Bork!
Also included is a series of complaint letters about Sesame Street's character The Count. Link