Rule #2: Online access

• Use online access for all your banking, investment and credit card accounts

This is another thing that really changed my financial life. Probably a no-brainer for most people by now, at least anyone who might be reading this site, but it's so much easier to be able to access bank accounts, investments, credit cards, etc. online. No more paper statements causing clutter and having to be shredded. I have repeating transfers set up between savings and checking to cover regular bills, and I save the cost of stamps by paying bills online directly from my checking account. And I time the payments and transfers as close as I can to the due dates, so I can maximize every one-millionth of a penny of interest I can earn in my savings account (and feel like I'm socking it to The Man).
I have a repeating reminder in my calendar to make sure I download and reconcile everything at least monthly, though I tend to download credit card transactions weekly. Again, it's seeing the spending and being able to analyze it easily with Quicken, that really motivates me to try to change my habits. Most major banking and investment institutions offer account activity downloads in Quicken's format, as well as Microsoft Money.
Online access has also particularly made a difference in how I understand my investment and 401k accounts, and really keep track of how they are doing vs. my bank accounts-- a good prompt to reallocate assets if they're not earning what they could be.