I've been freezing spaghetti sauce, M steak sauce, and plain tomato sauce. I've also been dehydrating tomatoes. If you haven't dehydrated tomatoes before, you really ought to try. I can't get enough of them. If you don't know how to dehydrate tomatoes, I wrote an article for (you guessed it) Suite101.
Tomatoes prepared and ready to dehydrate.
The final product - yummy!