Stink lizards

Stink lizards are animals sold by the pet store clerk at Joe's Ark Pet Store. They can be bought for 1 dollar each. There are approximately 500 sold. Fry considered buying a lizard as an Xmas present for Leela, but he decided to buy a parrot instead.

Quotes
[Fry whistles.] Fry: That's a hell of a good parrot. Although, I could get 500 lizards for the same price. Girls like swarms of lizards, right? Pet store clerk: Sir, the store is closing in two minutes. Fry: Alright, I'll take the 500 lizards. No, wait, yes. No. Yes. Yes. Yes! The parrot! Fry: Leela! Oh, my God! You saved my life. I am gonna get you so many lizards!
 * Pet store clerk: The lizards are a buck each, the parrot is $500.
 * [After Leela saves Fry]