I normally just double the check amount (not literally of course) to get the 20%

$30 gets a $6 tip unless they are just plain bad

If I'm there for three hours drinking beer and eating....Minimum $10 for that long of service no matter how cheap the bill is

I'm with most others regarding the checks...The waitstaff should ask right before running the tickets

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Dr. Spaceman: Now Jenna, medically speaking for your height your weight puts you what we call the "disgusting" range. Fortunately there are solutions. For example, crystal meth has been shown to be very effective. How important is tooth retention to you?