This method is popular with ultralight thru-hikers and requires two materials that you don't normally carry (cord and carabiner). Like all bag hangs, it can be foiled by smart, food-conditioned bruins. Check regulations to make sure bag hangs are legal.
A cheap, simple solution for secure tent-pitching on snow or sand. Note: The dowels work better for snow. However, by using a small disk (something like kid's play dishes), you can get the same effect for sand.