YNAB
YNAB is very goodfree personal budget software. The OpenOffice version is a spreadsheet which means that it’s much more malleable than a stand-alone program. You can add additional sheets to calculate your custom monthly budget. You can add scratchpad for rough calculations, while with the graph sheets you can get all the pretty pictures representing your budget. The beauty of this is that you can only do the graphs you need, so you won’t have to pay for a whole lot of functionality that you don’t need. With budget software, budgeting becomes not only doable, but almost fun. I’ll let you know in six months time how it’s going.