I'm particularly proud of this one-

Short story really, but at the end of a semester abroad in Tokyo, I had to surrender my alien registration card at my point of departure (in this case, NRT). However, I accidentally passed through immigration without having done this. I hurried back to passport control, which then admonished me about it and proceeded to place a "CANCELLED" chop over that first exit stamp. Back in Japan...for five minutes. The officer went into the back office, took care of something, then stamped me out again.

That is at the other end of the spectrum of DPS (Bali) immigration officials, who wouldn't even let me leave the country...