You should tip the waiter $10, minus $2 if he tells you his name,
another $2 if he claims it will be His Pleasure to serve you and
another $2 for each special he describes involving confusing terms
such as shallots, and $4 if the menu contains the word fixin's. In
many restaurants, this means the waiter will actually owe you money.
If you are traveling with a child aged six months to three years, you
should leave an additional amount equal to twice the bill to compensate
for the fact that they will have to take the banquette out and burn it
because the cracks are wedged solid with gobbets made of partially
chewed former restaurant rolls saturated with baby spit.
In New York, tip the taxicab driver $40 if he does not mention his
hemorrhoids.
-- Dave Barry, The Stuff of Etiquette
