GnuCash

If you recoil in horror at the bloat of financial programs such as Microsoft Money and Quicken, GnuCash may suit your needs. It’s a slimmer version of those programs, and it has all the features I need for managing my meager amount of money.

The interface is easy enough to understand. It actually looks a lot like a digital checkbook ledger. Don’t be fooled, though - GnuCash can handle the needs of much more demanding users.

http://www.gnucash.org/