1. Capture everything. If you're not doing this already, we need to talk. If you are, make sure there is nothing floating around in your head come the close of business before the holiday. Nothing ruins a good meal more than trying to keep from forgetting something that you can't address until Monday anyway.
2. Assemble your to do list for when you get back to work. It doesn't need to be a full list...I only have five items on mine, but they are five items that will get me back into the swing of being productive quickly. (FYI - Checking my email is NOT one of them.)
3. Inform your contacts of your productivity plans. If you are managing the expectations from others you should be reaching out to them so they're not surprised when you're not available at 8:30 Thursday night.
4. Use the time off to manage some personal expectations. Get some reading done, work on a hobby, fix something around the house. Keep a sense of accomplishment flowing beyond successfully eating three helpings of pie. I'm not saying you should go whole hog into a project, but that little bit of forward momentum will help stave off the inertia of the holiday.
5. Revel in the success of others. Holidays such as Thanksgiving are times to enjoy the company of friends and family. Before the food coma sets in and you descend into the depths of professional football, ask your companions and family members how they have been productive lately. Use this as inspiration for you as you drift off into that turkey induced nap...
Most importantly, take time to clear your head and rest your spirit. No one can be productive when they are on edge, over stressed, or just burnt out. Be thankful for what you have accomplished and the opportunities you have in the future to accomplish more.