Thirteen of something plus a sexual favor
I picked up those cookies from my coworker last night and got a baker's daughter's dozen.
An unnecessarily large collection of any particular thing
A shit-ton
"My uncle Joe has a hoarder's dozen of toilet paper, it was stacked up in his linen closet, floor to ceiling!"
"I just ate a hoarder's dozen of pancakes."
"I would give a hoarder's dozen just to see him again."
Bagel Shop Person: How many bagels do you want? Is a half a dozen good?
Shopper: Nah that's too many! A midget's dozen will be good.
Bagel Shop Person: A what?
Shopper: A Midget's Dozen! That's 5.
A group of 12 hairy men with a hairy 13th man as their leader
See Hairy 12
That Hairy Baker's Dozen is a good looking group of dudes
When an 18-wheeler driver's wife cheats on him/her in an orgy with eighteen other men.
After accidentally driving through the wall, Larry found his wife in a Trucker's Dozen with the neighborhood watch.
Four beers for Twelve Barbados Dollars
Bartender, give me a Bajan Dozen of deputy (deputy being the brand of beer)
69.
"That looks like a Biker's Dozen."
"You mean Baker's dozen?"
"Nope."
"How many is in a Biker's Dozen?"
"69."
"Nice."