Pocket Lint... Do a search for Mac finance apps and you'll find a truckload, all with one major flaw in common: they assume you have money. Pocket Lint makes it easy to calculate just how terrible your current financial situation is, with robust monthly expenditure tracking, easy income reporting (optional), and other powerful features. It even includes a tool to check the current eBay auction value of the Mac you're running it on, so if things get really bad you can always pawn your computer in a last-ditch effort to make rent.
Mac OS X 10.4 or later
*Previously available here