I always do.
Nice face bonus: $1
Nice legs bonus: $1
Short skirt bonus: $2
Nice butt bonus: $1
Nice rack bonus: $1.
Cutey-pie bonus: $5
Sweety-pie bonus: $5
It's a dude bonus: -$5
Wedding ring bonus: -$5
Actually, I made all those up now, but my mind does go through a similar process. Except for the dude and wedding ring thing. I don't really care about that.
In all seriousness, I tend to overtip no matter what kind of person it is. The only real bonus I count is how tired she looks. One time my buddies and I were in a diner late, getting super poor service the whole night, when we were one of the only tables filled.
But I could see it in her eyes, how flustered and exhausted she was. My friends all left as little as they could, but my friend Abe Lincoln and I thought differently.
Another time, in the front office of my building, torrents of angry people were yelling at the cute asian girl who was the only one there. On top of everything, she was having trouble with the computer. Well, there nothing I hate more on the job then looking like an idiot to the customer, not knowing how to do what I'm paid to. I was pretty pissed myself that day. It was just a day for being mad. But the poor thing was way too sweet to be mad at. It was actually pleasant waiting for her to figure it out. She congradulated me on my patience.
Yes I'm bragging.
I usally round up when I do the tip. I've been known to lose close to $20 on a $10 meal. Working in the restaurant business sucks. That's all I can say. Unless she talks back, throws your food at you, spits in it right there, or acts like she hates you, I tend to leave more than I should.