A segment of
Mystery Science Theater 3000 wherein the
Joel & the Bots exchange
invention prototypes with
Dr. Forrester and
TV's Frank.
The inventions are always incredibly silly; Joel's are usually whimsical and lighthearted while the Mads's inventions tend to be a bit more malevolant, although ultimately harmless.
When the inventions are good (Like the "Cartooner" - "Ziggy had Garfield neutered?!") the can be among the funniest parts of the show. Good fun all around.