Cha-Ching is a wonderful money-management application for the Mac (don’t worry, it’s a universal binary so it’ll work on any Mac). The interface is done beautifully and definitely fits in with the look of OS X. ChaChing provides all the features you would expect from a money-management application including bill and account management, and thanks to the fact that the application supports the iCal standard, you can add your upcoming bills to your calendar so you’ll never get a late fee again. All events are (of course) categorized with tags you can add yourself, and if you want, you could even add images to each item.
Cha-Ching will run about $25, and is unfortunately available only for the Mac.