One thing that would be cool for the anniversary would be if PBS or Sprout would show a classic clip between programming. Maybe something under two minutes.
Of course, if classic clips were shown between programming, I guess they'd be some of the best-known classic clips. Stuff like Rubber Duckie, C is for Cookie, I Just Adore Four, Bert's Bust, Kermit and Joey Sing the Alphabet, the original What's the Name of That Song?... But if there were showings of one classic clip between each program, I wonder if they would show clips without any recurring Muppets, or any animation or film inserts, or any non-Muppet clips with the humans. I also wonder if they would include any really obscure early clips, such as clips with early versions of Big Bird, Oscar, Grover, and Snuffy, or Matt Robinson or Hal Miller as Gordon.
And for something like this, I can think of a way to work around the full frame issue: Put in a special "border" over the clip, perhaps put in a 45th anniversary logo on top and maybe include a fact track below the clip.