I don't know why but I really love mechanical gags, gags where the characters engaged in some repetitive, mechanical action, become aware that something is wrong but find that they are powerless to stop it because they are bound to this mechanical action.
Ernie Kovacs' "Nairobi Trio" is a great example of a "mechanical gag".
Another is The Muppets' "Mahna-Mahna", which Shane and I spent New Year's Day studying and enjoying in several forms...
My favorite version of the gag from The Muppet Show, Episode 101 Host:Juliet Prowse, April 25, 1977.
The original Sesame Street version from 1969.
This was performed live on The Ed Sullivan Show three days after the debut of the Sesame Street version. This is fairly similar to the one they did eight years later on The Muppet Show, but this version has live audience reactions instead of a laugh track.
A call back with Sandra Bullock from Muppets Tonight, June 23, 1996.
My new favorite D.I.Y. version.
And a version from the UK version of The Office.