And the monkeys will fly out of my ...

Recently I have came across* a saying which gave me a lot of trouble*. Namely, I wanted to look it up* but no 'paper dictionary' had it. Of course the bottomless* Internet offered me an explanation. The saying I'm talking about is:

...yeah, and the monkeys will fly out of my butt*!

e.g.

-"I think I will stop spending so much money" 

-"Yeah, and monkeys might fly out of my butt"

When you think about it, the meaning is quite obvious - we use it when we want to underline the fact that what somebody has said is more than impossible ;) just like the fact that monkeys will fly out of anybody's butt :) (This meaning reminds me of another saying - (till) hell freezes over.) What is more intersting is that this saying originated from a film entitled "Wayne's World" starring Mike Myers:

The saying entered English language shortly after the film's release.

What would we say in Polish?

How about: tu mi kaktus / palma wyrośnie?

(BTW* - if you have any other ideas how to translate it into Polish, be my guest and post them in comments)

Glossary:

came across - natknęłam się na

gave me a lot of trouble - nastręczyło mi sporo trudności

look it up - sprawdzić (znaczenie) w słowniku

bottomless - bez dna

butt - tyłek

BTW - by the way - przy okazji