gnucash.org
GnuCash is personal and small-business financial-accounting software, freely licensed under the GNU GPL. It is available for GNU/Linux, BSD, Solaris, Mac OS X and Microsoft Windows. It allows tracking of bank accounts, stocks, income and expenses, and is based on professional accounting principles for balanced books and accurate reports. Feature highlights include double-entry accounting, stock and mutual fund accounts, reports and graphs, and QIF/OFX/HBCI import.