For Thanksgiving (& anytime!) use a smaller plate. That way, if you clean your plate, and/or take 2nds, at least it is a smaller portion than you used to do.
To eliminate temptation during Halloween, I only buy candy I don't like (so my husband will eat it and I'm not tempted).
Then, I take any leftovers to the office so they can overeat!
My worst splurge for calories is drinks with friends. I need to have more "H2O on the rocks" instead of a martini or in-between drink orders.
When things get boring and you are in a rut, change it up! I find it a welcome change to have breakfast for dinner, dinner for lunch, and lunch for breakfast. Switch it around and see what happens. It might make you think of some changes to your meals that you hadn't thought of previously.
Whenever dining out at a mexican restaurant I will ask for salsa instead of salad dressing. It is fresh and I don't have to worry about portion.
For crunch on my salad at home or at a salad bar, I have sunflower seeds instead of croutons. Adds protein and "good" fats.
Hope this helps...