I would guess ferrets do laugh - I know they enjoy having their tummies
tickled. Researcher Jaak Panksepp has studied rats and says they laugh.
He has measured laughter "in the form of high-frequency 50-kilohertz
ultrasonic calls, or "chirps," that are distinct from other vocal
emissions in rats."
<http://www.scientificamerican.com/article.cfm?id=rats-laugh-but-not-like-human>

Patti
Otter - Dad tickles better than Mom
Critter - I'd rather have my back scratched
Dodger - You have to catch me first
Teddy Bear - It's pretty easy to catch you when you run right back!

[Posted in FML 7670]