Here's another super simple Rethink/Refuse/Reuse that you have no excuse not to be using at home. It requires no craftiness whatsoever and is just a simple matter of making the most of the resources that make their way through your life.
Some extremely eco-minded folks avoid takeout containers entirely (I've read accounts of brave people showing up at restaurants with their own reusable containers) but, I have to admit, I am not one of them. I cook a lot, but I like to treat myself to other people's cooking occasionally, and this usually happens when I just want the easiest solution possible. So, like most people, I get my takeout in disposable containers.
It turns out that foil takeout trays fit perfectly in my toaster oven and make great mini roasting pans or cooking trays. I wouldn't buy them at the store, but if I have a few leftover from takeout orders, I wash them out and re-use a couple times. (Then if I cook something extra dirty or gunky, I can toss the container without too much guilt, since I already gave it a few more uses than it was originally intended for.) They are particularly suited for dishes you might want to make ahead, keep in the freezer, and bake later (mac and cheese, anyone?) - you can leave them in the freezer as long as you need to, and won't miss the containers like you would your favorite Pyrex baking dish.
(Bonus: the #6 clear plastic tops make great trays for paint or glue, for those of us with a crafty bent. And in one of my personal favorite little-known RePlayGround facts, they are made of the same material you'll find in Shrinky Dinks, so save them for a project!)
We can't be all green all the time - sometimes it's the little things that add up to big changes.