I am proud today to release version 0.3 of wxBanker, a free, simple, lightweight personal financial management application for Linux, Windows, and OSX! It is written in Python and wxPython.
It is basically like the concept of the checkbook register brought into the 21st century, allowing you to keep track of balances and transactions across multiple types of accounts. It allows you to know the balances of your accounts without relying on your bank or credit card online interface, which is often slow to update and can't take things like uncashed checks into account. Not to mention that entering each transaction into wxBanker makes spending money with debit/credit cards more tangible and can help keep your spending in check. You can also keep track of "virtual accounts" like loans to/from friends, accounts receivable/payable, and allocate funds for specific purchases like a new computer.
You can also search your transactions to see how much you have spent in specific areas, and see a graph of your balance over time. Check out the screenshots below:
If you find GnuCash too complex for your purposes and decide to take control of your finances with wxBanker, let me know what you think! In Ubuntu you should only need to install python-wxgtk2.8 and python-numpy. Project page: https://launchpad.net/wxbanker.