I know that this seems very out of date (and slightly anal retentive), but I keep track of all of my expenses in a checkbook register.  I try to save all of my receipts, write them into the register, and then check them against my online banking statement about once a week or so.

I’ve found that there are two benefits to this. First, there have been more than a few times when I’ve caught an overcharge, especially at a restaurant, that I wouldn’t have noticed if I hadn’t kept my receipt. A quick call to the restaurant usually straightens everything out.

Second, just the act of writing it all down really gives me a sense of where my money is going, even more so than just seeing it on a computer screen. I have to face the fact that I somehow spent $50 in cabs over one weekend, or that I keep on racking up ATM fees. This is not for everyone — and, to be sure, I don’t even keep up with it all the time — but it certainly helps.

- Julia