Ahhh, there's nothing like rolling out a lab of shiny new PC's, and watching as the first batch of users comes in to "christen" them.
I pop out to the gents, and someone is in the stall downloading some rather pungent brownware. This friend of humanity finishes his ablutions, walks out without washing his hands, and heads straight to my lab full of new shinies.
If that isn't bad enough, he pulls something out of his bag... A (now-lukewarm) pie from the Spar, and proceeds to eat it over a brand-new keyboard.
I instantly decide that the dirty interloper and his flaky (pastry) sidekick have outstayed their welcome...
"Excuse me, are you illiterate, blind or just plain stupid ?!"
"What's the problem ?"
"You're EATING A PIE right under a sign that says 'NO FOOD OR DRINK TO BE CONSUMED IN THIS LAB' !"
"That's right, I am !"
He then eats the pie in the messiest, noisiest way possible (think Cookie Monster - Omnomnomnom), dropping gravy and bits of pastry all over the keyboard, then logs out and walks out leaving a huge trail of pastry flakes in his wake. The only way he could have made matters worse would have been to lickthe gravy off the keyboard.
A four-week ban and a bill for a new keyboard rapidly wiped the smile off his face.