According to the TSA, we can now take travel size toiletries (3 oz or less) in a carry-on, if you can fit them all into a quart size bag. There's 32 flouid ounces in a quart. Yay! REI sells a set of nalgene bottles that are square would probably fit in a quart zip bag.
Yay for allowing a small amount of Liquids, Gels, and Aerosols! You can also bring on beverages purchased after the security checkpoint.