Here's another one I haven't heard anyone mention, starring Grover. It's a spoof of the classic novel writen by Ernest Hemmingway, The Old Man and the C (spoofing on The Old Man and the Sea).
Grover appears wearing an old fisherman's hat and white beard inside a boat. He's talking about why he loves the C, and all the while the camera starts panning downwards to show Grover in his boat atop a red letter C.