This is fun: here's a "tip" posted on Reddit in which the server is given a lesson in "Waitressing 101." The cocktail napkin note reads as follows:
"Don't tell every customer you're very busy to excuse your lack of serving skills. Your job is to attend to us, not make us feel like we are an inconvenience. A little bit of personal attention goes a long way; in the form of a tip.
Just my two cents."
And then they left two cents. Get it? Anyway, whoever left this note is certainly not alone — one third of Americans won't tip on crappy service — but sassy tips like this have had a tendency to backfire in the past. So be careful out there, jerks.