I never knew this existed in New Vegas even though I probably have about 500hrs in it give or take. Makes me wonder what other things I could have missed. can't say I ever used shotguns though.
The Humble Cudgel is the unique iron pipe hidden in the sewers beneath Camp McCarran and is a reward for completing an unmarked quest Cajoling a Cudgel.
It deals 4 more damage and uses 3 less AP than the standard iron pipe- making it totally useless.