CNN Money, which doesn't seem to be as obsessed with missing airliners as the mother network, has an article about folks you don't think about tipping, but should.

Maybe I'm just a cheapskate, but really? The article lists your exterminator, the cable guy, your spray tanner, and a couple of others.

(Photo by Tim Boyle/Getty Images)

I understand tipping for service, but at what point does it change from tipping for something special to tipping simply for doing one's job? If you cut hair, a skycap, restaurant server, yes, of course. And I understand, many folks are working for around minimum wage. But I pay for most everything with a credit card, and there's the little slip of paper with the blank tip line. If I'm at the counter at a coffee shop, and you just handed me a to-go cup of coffee, isn't that your job? But leaving the tip line blank makes me feel so guilty. You, too?

(Full disclosure: When I do tip, I tip 20 percent, so I'm not just a grumpy old tightwad. I'm just grumpy.)

The article mentions there's other types of tips, like a glass of water for the cable guy, but that's just seems to lead my mind to stuff I read in Penthouse letters when I was a teenager.

I guess let your conscience be your guide, but I don't like feeling guilty.