"They're noted for their hiding," Rincewind offers. "Among other things. Marbles sound fine. Except I'll probably lose them."
Rincewind tries to wriggle his fingers, just to check on them.
Rincewind gulps, not liking that dreamy tone at ALL. "Yes, I know. I've tried and tried," he sighs. "Those big black flappy things with teeth?!" Rincewind squeaks. "No thanks! How about a library?"