The automated ones that you can leave a message on are fun:
"Hey, thanks for calling but I don't live here, I'm a burglar."
"I dunno, I'm only three-and-a-half years old."
"Moo? Moo moo moo, moo moo, moo moo moo."
"Aagh! Help me, please! He's got a gu-" (
click)
"
"
You get the idea. Fun with live telemarketers, too.
