Ordinarily I would be against it. I've never tipped a plumber or other repair guy - in fact, I always have to calm my wife down after she sees how much they charge for such a small amount of time.
But I've just experienced a guy who operated on my table like it was his own, put in a huge amount of time to do it right, taught me a lot while he was doing it, and didn't charge that much to begin with. With this kind of guy you want to do something to show your appreciation. That guy, no surprise, was Realkingcobra.
But I still hid the tip from my wife. :grin-square: