(Sexy, slow female voice
oooOOOO, Greg's in... OOOOooo,
Greg's out... ooooOOOOO, Greg's in... OOOoooo, Greg's out...
ooooOOOOO, Greg's in... Humph, Greg's busy, you had better call
back later...
or
The machine answering this message is connected to a 5000 volt
power supply, and a relay which is wired to this small kitten.
(Sound of a kitten meowing.) If you hang up before you leave a
message, it will complete the circuit and fry the kitty. The
choice is YOURS!
(both from the net)