When I want to balance a checkbook I use a spreadsheet program. supercalc 7 works well enough for that purpose and I can do additional kinds of calculations like figure out each time my pay rate changes at the beginning of the year how much house I could afford on that pay. Also what the effective tax rate turns out to be is easily enough done. Other accessible spreadsheet programs exist like oleo that are also under the copyleft license too. If I don't want to use a spreadsheet even with all of its advantages, I can easily enough fire up dc and use that. I think there's a way to make dc calculate like a regular calculator too. At least I got that working once.