This morning, I overslept, so I took a cab in.  I think without question, cab drivers are the most appreciative of tips.   No one must be tipping these guys more than just rounding up to the next dollar.  They're driving around for hours and hours all day, and I'm sure cabdriver economics aren't too good...   so I like tipping them.  You know who doesn't really appreciate tips and it drives me nuts?  Coat check people.  I hate coat check.  I hate checking anything.  If I wanna lug around all my crap, that's my business.  Blocks the aisles?  I'm notoriously underdressed for winter and I'm sure I usually have the thinnest coat in the room... not to worry there.  Valet is ridiculous, too.  With both the coat check and the valet, if my item is in plain sight, you're not providing a service.  So many times I'm in coat check and I can just reach over and take my coat b/c the booth is so small, but still, they have to hand it to me and its going to cost me a buck or two.  Coat tax.  That's what it is.  I'm being charged for dressing appropriately for the weather, which I barely accomplish anyway.  And coat check people for the most part treat it like its normal.  Its not even a tip anymore.  Its a charge. 
Tipping in restaurants is a broken system, too.  I will definately tip well for great service...  20-25%... but I'll be the first one to admit that it really doesn't have the desired effect unless you're a repeat customer.  It works in Gino's, because we're there all the time, but if you're a one shot deal, that's never going to do anything but show appreciation, and I sort of think there should be some kind of feedback loop there that improves my service.  Maybe we can do some kind of loyalty card service for all restaurants where, when I check in, the waiter or waitress gets my average tip and the variance in it.  He or she would see that my average is solid, but my variability is above normal--meaning that if you take care of me, I'll take care of you, but if you're rude to me, its going to cost you.  Otherwise, most times the server doesn't even see what you gave them while you're still there anyway, so it doesn't really have the desired effect. 
What really has to stop are the bathroom attendents.  I haven't seen to many, but if I do, I turn right around and decide I don't really need to go that badly.  I refuse to legitimize that scam.  I've been using the bathroom by myself my whole life... I don't need any help now.  I'm a New Yorker.  Just leave me alone and let me do my thing.  Don't help me unless I ask and don't hold my coat for $2 ransom.