It sounds daft, but I use Excel! It works fine for me, I've got different worksheets for each bank account, and it's dead easy to use internet banking to download each months data (or copy and paste from the transaction view) and paste it into each sheet. You can do loads of calculations, but all that depends on being able to use Excel.
Another couple that Google threw up which looked worth investigating include Moneydance 2008 (
http://moneydance.com), Quicken (
http://quicken.intuit.com/personal-finance/) which is an old player in this market, and quite a few companies are now offering hosted solutions (i.e. you use an online web based application to manage your finances).
If you're on a budget,
this is worth checking out too