Stop smoking pot.
Srsly, I hate when I get all nommy at night. It's the worst. Sometimes I ride it out, sometimes I can't. Pretzels dipped in picante or salsa usually do the trick for me. Utz pretzels (don't know if they're just a local brand or not) has a sourdough specialty pretzel that's really nicely salted. A serving is 5 pretzels for 110 cals. I make sure I portion them out, rather than just hauling the bag and eating from that, and drink a big glass of water with them.