Maybe you could set up a cut off time. I tell myself no food after 8pm. That means everything, dinner and dessert which is normally a cup of tea and some cookies. After that it's water all the way and if I am truly hungry then I have a glass of milk before bed so I don't get heartburn all night from an empty tummy LOL. whatever time suits you though, it should be no less than 2 hours before you go to bed to give the food a chance to get burnt off.
Boredom eating is a pain, I've been doing it a lot on the weekends and really there's so much that has to be done around here, but somehow I manage to talk myself out of doing it and sit and eat instead.
You could look at what you're eating for arvo tea and dinner and try to swap things over to Low Gi, or maybe a few more carbs which keeps you fuller for longer.
If it's more of a habit that you've formed and boredom then Kate's got some fantastic suggestions up there for finding things to do. Sometimes I'll tell myself that if I',m feeling nibbly I have to sweep the house first (takes a good half an dhour) and if I'm still hungry then at least I've burnt it off before I eat it.