Hilarious! When your credit card signature fun backfires

Manager: OK, I'm going to decline the signature and have you sign it again.
Manager: Sir, your signature...heh...umm...doesn't match the signature on your card.
Kingpin: I know and there is a good reason for that.
Manager: (quietly) You drew a penis on my credit card machine.
**The guy behind me bursts into laughter.**
Kingpin: Yeah, I didn't think this would happen. I've been trying to see how far I could go with my signature before the credit card company did something about it.
Manager: I guess you learned your lesson.
Kingpin: Yeah, the credit card doesn't accept penis.
**The guy behind me now can't stop laughing.**
Kingpin: Fair enough.
Manager: This time, really sign it.

I thought the story on the above site was hilariously funny!