I have been a customer at a dive shop near me for about a year and a half. The owner was my high school biology teacher. Him and his son run the shop and we seem to have become quite friendly. Although thay are basic local shallow water dives, myself and sometimes my brother go with them just for the hell of it. Their dive master is a retired NYC fireman and he's a great guy too. With the exception of my actual open water dives, I basically dove on my own with my brother, never with anyone from the shop, just on their boat.(everyone seems to do their own thing) I've never tipped the DM until this weekend. When we go out, we seem like a bunch of friends, although I do pay to go out. This weekend I went out by myself and the DM dove with me. Thats when I realized I had not tipped him before and I feel really guilty. I was playing with my new strobe and he stuck with me. We always brought beer etc (heineken is the DM's favorite). All the other boats I've been on I've tipped the dive master because thats what supposed to be done. It seems stupid but it really bothers me, he propably thinks I am a cheap SOB. What do you other dive masters (and divers etc) think? Theres not much of a point to this post other than I would like to try and do something for him.