Adding my two cents in here.
I've served at 4 different restaurants in the past 5 years, and we DO NOT make minimum wage. We make $2.13 an hour and all of that goes to taxes so our checks are usually $0.00. I work at a restaurant where I have to tip out 9% of my TOTAL sales to the chefs there, not to mention the bartenders and bussers. Meaning: if you come in my restaurant and rack up a $50 bill and leave me no tip, I have to take 9% of that out of my own pocket to pay for the chef that cooked your food. Basically, I served you for negative $5 and you were probably rude as hell and made me run my ass off on top of that. Also, poor service isn't always the actual servers fault. We rely on bartenders, chefs, kitchen help and others to get you what you need and sometimes it doesn't always work out right. Servers tend to be the ones who always get blamed, though.
That being said, I love it and I hate it. I worked today for 5 and a half hours and walked out with $180. It has it's pros and cons just like every other job.
I tip 20-30% on any service I receive (salons, restaurants, deliveries, taxis, etc.) and if you were awesome, I'll tip more.