I've found that the more organized I am, the more money I save and let's face it late fees are a waste of money. I have a notebook I keep by my computer with a "to do" list and also a page listing bills and credit cards that are paid monthly and add a check mark and date when I pay them. It's also a good idea to copy the confirmation code (if you pay online) and add that to your check register or program (I use MS Money).