If you're looking for a quick education in double entry bookkeeping look no further than GnuCash[1]. It will ease you into the "Assets - Liabilities = Equity + Income - Expenses" accounting equation and help you keep tabs of your budget without using the categories commonly used in commercial personal finance applications. There are many other competent and perhaps easier to use personal financial packages including AceMoney Lite[2], Grisbi[3], jGnash[4], KMyMoney[5], Metalogic Finance Explorer[6], and rq money[7].
Mint[8] also looks like an attractive personal finance service. However, you'll hesitant to give your banking details to any service in the cloud even though they promise "They ask for your online banking user name and passwords, but they do not see or store that information.
[1] GnuCash
Website: http://www.gnucash.org/
Download Link: http://sourceforge.net/project/showfiles.php?group_id=192 or http://www.gnucash.org/pub/gnucash/sources/stable/
Author: The GnuCash Project
Current version: 2.2.4
Version date: 3/3/2008
License: Free - GNU General Public License (GPL)
Download File size: 52 MiB
Operating Systems Supported: Windows, Mac OS X, Solaris, BSD, GNU/Linux
Additional Software Required: To install on a non-Windows OS, users will need Gnome 2, guile, and slib.
64 Bit Capable: Yes
Portable Version Available: No
Non-English languages supported: Handles internationalized dates and currencies. The Gnucash menus and popups have been translated to 21 languages, including Chinese, Danish, French, German, Hungarian, Italian, Japanese, Norwegian, Polish, Portuguese, Russian, Spanish, Swedish, Turkish, Ukrainian, and British English. Documentation is available in English, French, Portuguese and Spanish.
Other relevant information: You're encouraged to use an encrypted file system to store your critical data files.
[2] AceMoney Lite
Website: http://www.mechcad.net/
Download Link: http://www.mechcad.net/downloads/AceMoneyLiteSetup.exe
Author: MechCAD Software LLC
Current version: 3.10.2
Version date: 4/6/2008
License: Free - MechCAD Free Software License Agreement
Download File size: 1.76 MiB
Operating Systems Supported: Windows XP/200/Me/9x
Additional Software Required: Emulation software supports operation on non-Windows OS(Linux with Wine, Mac with Crossover)
64 Bit Capable: No
Portable Version Available: No
Non-English languages supported: 40 languages, 150+ currencies
Other relevant information: AceMoney Lite works with one user account only.
[3] Grisbi
Website: http://www.grisbi.org/
Download Link: http://grisbi4win.sourceforge.net/www/download.php?lng=en
Author: Grisbi Team
Current version: 0.5.9
Version date: 8/18/2006
License: Free - GNU General Public License (GPL)
Download File size: 9.25 MiB
Operating Systems Supported: Windows, Mac OS X, Debian, Fedora, FreeBSD, Mandriva, Nokia 770 Internet Tablet OS 2006, Slackware, StartCom Enterprise Linux Multimedia, SuSE, Ubuntu, Zaurus, Zenwalk
Additional Software Required: GTK 2.6+ (included)
64 Bit Capable: Yes
Portable Version Available: No
Non-English languages supported:
Other relevant information: 0.6 version will be almost rewritten from scratch
[4] jGnash
Website: http://jgnash.sourceforge.net/
Download Link: http://jgnash.sourceforge.net/wiki/index.php/Download_Page
Author: Craig Cavanaugh et al. (see Help > About > Credits tab)
Current version: 1.11.7
Version date: 2/5/2008
License: Free - GNU General Public License (GPL) version 2 and others (see Help > About)
Download File size: 6.32 MiB
Operating Systems Supported: Windows, Mac OS X, Linux
Additional Software Required: Java 1.4.1_02 or higher
64 Bit Capable:
Portable Version Available: No
Non-English languages supported: Many Locales and currencies supported
Other relevant information: File Encryption
[5] KMyMoney
Website: http://kmymoney2.sourceforge.net/
Download Link: https://sourceforge.net/project/showfiles.php?group_id=4708
Author: Michael Edwardes, et al. (see The KMyMoney Handbook Chapter 21)
Current version: 0.8.9
Version date: 3/24/2008
License: Free - GNU General Public License (GPL) version 2
Download File size: 6 MiB
Operating Systems Supported: Linux and FreeBSD (any OS with KDE 3.2+)
Portable Version Available: No
Non-English languages supported: Danish, French, Germany, Italian, Portuguese, Russian
[6] Metalogic Finance Explorer
Website: http://www.metalogicsw.com/
Download Link: http://www.metalogicsw.com/financeexplorer/index.html
Author: Metalogic Software
Current version: 3.1.3
Version date: 12/16/2007
License: Free - Metalogic User License Agreement
Download File size: 1 MiB
Operating Systems Supported: Windows
Additional Software Required: No
Portable Version Available: No
Non-English languages supported: No
[7] rq money
Website: http://www.rq.sk/rqmoneyen.html
Download Link: http://www.rq.sk/download.html
Author: Slavomir Svetlik
Current version: 1.0
Version date: 3/15/2008
License: Freeware
Download File size: 725 KiB
Operating Systems Supported: Windows Vista/XP/2000/9x
Portable Version Available: No
Non-English languages supported: Portuguese, Chinese, Czech, Hungarian, Italian, Polish, Russian, Slovak, Spanish
[8] Mint
Website: http://www.mint.com
Author: Mint Software, Inc.