Jerry-

My favorite Wisconsinism came at a department store when I asked for help from a clerk who was, unbeknownst to me, taking her lunch break.

"I'd like to help you," said she, "but I'm on my off."

(Second place goes to a golf partner who, after hitting his drive on a short par 3 pin high but into the sand trap on the left remarked,
"Damn, I got the right up but the wrong over.")

Worst part is, I knew right away what both of them meant.