I am not at all superstitious, but when gaming I absolutely am. I do have my lucky lid for use when I am getting pummelled.
Craps:
I always set my dice before rolling. I also have ritual when choosing my dice to throw. If a roller draws my ire for any reason, I'll either leave or bet don't come.
BJ:
Blackjack I prefer to play alone. I will leave immediately if a card gets bent, or the dealer makes a comment about the smoke. I also refuse to play auto shufflers.

I am not a slots player but if I should be walking by a slot and my hand starts itching, I play that machine immediately.