Lisa BB. wrote:

Picture it - a family dinner - my brother:

Before the dinner he opened the box of paper cups. Carefully made
some cuts in the bottom section. He put the cups back in the box so
our mom didn't know what happened.

Cups were on the table and then filled with punch. While still on the
table the punch stayed in the cups. People would take a full cup and
walk around and shortly thereafter, the punch began to spill out the
bottom.

A small company I worked for used those small plastic cups with a hard plastic
holder for their coffee. People were supposed to drop a dime in another cup on
the counter to pay for their coffee. The money started disappearing. Someone
finally figured out that someone was sticking a cup in a holder, setting it on
the counter, and filling up the money cup with coffee and walking away with it.
They used a pin to make a hole in the bottom of the money cup, and followed the
line of drips to discover the culprit.