freezer tip for hamburger or veggie puree

I found this post via tastespotting (a blog with gorgeous pictures from other blogs, a must see for foodies). In the post they have a method for freezing hamburger that I've never seen before. The hamburger is flattened down in a gallon freezer bag and then a chopstick is pressed down on the plastic to divide the bag into 9 portions. (see pic in link) This way you can get individual portions when you want them and roll the bag to store in the freezer if you don't have a place for flat bags in your freezer. They also suggest using this technique for rice, thick pasta sauces (should work for pesto), mashed or pureed fruits or vegetables, cookie dough, etc. The only one of those suggestions I think makes real sense is pureed or mashed fruits and veggies for single servings, to add small amounts to recipes (especially if you do the sneaking veggie puree into food strategy that is so popular now), or for baby food. Anyway, it seems like a good idea.