Better than the onions is the wine.
Don’t forget Tramampoline!
My new favorite fun word is concatenated.
I would like my lotto winnings in large denomination bills, please.
Almost anything silly translated into Latin. My favorite is “Quid Me Vexitebus,” which I’ve probably spelled incorrectly. I was told it means “What, me worry.”
Indian place names (we have quite a few here in WI):
Chequamegon
Mukwonago
Weyauwega
Shawano
Waunakee
It’s also fun to watch people who aren’t from around here try to pronounce them. 
I think Oconomowoc is my favorite in that regard.
Hoagie! Hoagie! Hoagie!
(Ask my poor assistant, she gets tired of me saying this. And now that it’s festival season, I’ve been taking pictures of the Steak Hoagie booths and texting them to her )
How do you titillate an ocelot? You oscillate its tits a lot.
I’d rather a bottle in front of me than a full frontal lobotomy.
Trampopolis, that midwestern mecca of big hair and Louis Vuitton handbags…
Favorites that have already been mentioned: Monongaheala and Oconomowoc.
I’m terribly fond of the Bulgarian word for “here you are”: zapolvyaidaite. It’s very satisfying to hand someone a pen with a nice “zapolvyaidaite!”.
[nitpick]
I’d rather have a bottle in front of me than have to have a frontal lobotomy.
[/nitpick]
Why do I know this? Years of listening to Doctor D, plus I once used the song as an audition for a part. (Yes, I got the part.)
Saxomophone…saxomophone…
“I’m a poet and I didn’t know it.”
Once I was riding with some friends from Chicago to Minneapolis and we passed Menomenee WI. For some reason we found this name highly amusing, and kept repeating it. Eventually, of course, we started singing it to the tune of M’nah M’nah.
Thrice
“If I want you to bunt, I’ll touch my belt buckle not once, not twice, but thrice!”
[nitpick]
I believe it is actually “I’d rather have a free bottle in front of me than a pre-frontal lobotomy.”
…but what do I know?
[/nitpick]
Taumatawhakatangihangakoauauotamateapokaiwhenuakitanatahu
Don’t forget the tubamaba!