You already covered my first bit of advice in your OP

I was going to suggest to recognize the difference between hunger and just wanting to munch. Which you've already done, so that's good.
When I'm sitting around and have the munchies I try to do some kind of busy work. Painting my nails, like many have suggested, planning my meals for tomorrow, playing online bingo (haha), etc.
Also, there are foods that are "safe" to munch on. Gum is helpful, but it doesn't always give me the satisfying hand-to-mouth motion, lol. I always keep some celery around. Personally, I can eat it without ranch or anything. And it actually takes more calories to digest than what it provides, so it's technically a zero cal food. And it satisfies me when I just want to eat something.