Best Ways to Organize Bills?

scorp1us asks: "Every year on the 1st of January, I start a new set of folders for storing my bills. Generally, I keep everything divided up by account. But this seems to take too long. I wait 3-6 months and get a big pile nad have to go about sorting it. I have been considering a per-month scheme - all bills go to one folder, each month. With all the CS people out there studying sorting algorithms, has anyone found a better approach?"