Kelso: Hey, Eric, I have to ask you a very important question. Can I borrow your G.I. Joe for a little experiment?
Eric: No.
Kelso: I thought you were going to say yes. And, by the way, the experiment was a success. G.I. Joe melts faster than cheese.
Eric: Kelso, you can't just take my things without asking permission.
Kelso: Come on, we're friends. I figured, what's mine is yours and what's yours is mine. What's Donna's is mine, too.
Donna: Kelso!
Kelso: Yeah, Barbie didn't make it either. No one likes to see civilian casualties.