When my website is back up, I'll post a link to a downloadable, super-easy Excel spreadsheet you can use to keep a bank registry (I teach our clients how to create their own registry as part of our computer class). I'm also working on one for OpenOffice, and will post that as soon as it's done.
Both are simple documents, but it's just a matter of disciplining yourself to keep track of when you put money in your bank account, and when you take it out (or when someone else takes it out, like with automated payments). Three minutes a day is all you need to do this.
With a spreadsheet, there are a number of advantages. The program still does all the math for you. Open Office is FREE, and does just as much and just as easily as any other spreadsheet program. Best of all, you don't need to log into a website to do any of it, but you'll still have that nice, cozy feeling of doing it on the computer.