So what do we eat at this time of year? Here some items that have a very good chance of showing up that you can focus on.
Turkey- Pretty much guaranteed. Its low/no carb and so you can eat as much as you like, the down side is you will be sleep drugged through the rest of the day.
Salad- Its obvious, but it fills your plate.
Broccoli Salad- Seems like a staple for a pot luck. Someone will usually make it, and depending on their recipe it can be pretty low carb. Try a little. If it not too sweet your probably OK.
Fruit- If it the low sugar kind go for it.
Green Beans Casserole- It's not the lowest in carbs, but its not the worst either.

Beware the silent killer. Ham. Not all ham is bad. Matter of fact most is good and low in carbs, but if you happen to get Honeybaked Ham or one that has a sugar coat on it, they can be very carb heavy and contain a lot of sugars. So beware. They see innocent enough, but turkey may be much safer.

Oh and of course, just avoid the dessert table. The only thing you will get from going near it is remorse.
Anyone else have any good tips?