GnuCash - A personal and small-business financial-accounting software, licensed under GNU/GPL and available for Linux, Windows, Mac OS X, BSD, and Solaris.
Quicken - Stay in control of your monthly cash flows, budgets, and expenditures. Quicken provides a navigable interface where you can organize your debit, credit, and savings, and build good habits accordingly.
Xero - Xero is online accounting for your small business.
Buxfer - Online tools for personal finance, budgeting, and bill reminders. Split bills and IOUs with friends and roommates.
CheckStream - CheckStream check printing software
Money Manager Ex - Money Manager Ex is a free, open-source, cross-platform, easy-to-use personal finance software.