12. SamuraiWant to see how well your Web applications would stand up to an attack? Samurai collects some of the best open-source testing tools available in a single package. Operating System: Linux.

Document Management

13. LogicalDOC

LogicalDOC makes it quick and easy to set up a Web-based document archive so that you can store, search, and organize your files. Features include scanner support, document signature, version control, and more. Operating System: OS Independent.

eBook Organizer

14. eLibrary

This app makes it easy to organize, tag, and search your eBook collection. Input book information manually, or it can automatically find cover art and other info for you. Operating System: Windows.

e-Commerce

15. PrestaShop

With more than 30,000 active community members, PrestaShop has quickly developed quite a following. Key features include scalability, an intuitive interface, and lightweight size (around 6 MB). Operating System: Windows, Linux, OS X.

16. Open Auto Classifieds

Designed just for car dealers, this application makes it easy for the non-technically inclined to set up an online vehicle listing with minimal expense. Operating System: Windows, Linux, OS X.

Games

17. Rigs of Rods (RoR)

This truck, car, airplane, and boat simulator uses a unique soft-body physics engine, which makes the simulated vehicles more flexible and lifelike. Create your own vehicle or drive one of the more than 2000 vehicles that other users have already designed. Operating System: Windows, Linux.

18. Solitaire Greatest Hits

Free solitaire card games for the Mac. It includes Klondike, Free Cell, Spider, Pyramid, Canfield, Aces Up, Golf, Scorpion, Yukon, Baker's Game, or Forty Thieves. Operating System: OS X.

19. gbrainy

This app aims to keep your mind sharp, no matter what your age. It includes logic puzzles, mental calculation, memory trainers, and verbal analogies. Note that while there is a Windows version, gbrainy was developed for GNOME and works best for Linux users. Operating System: Windows, Linux.

20. Brain Workshop

Brain Workshop uses the Dual N-Back mental exercise to help you improve your short-term memory and fluid intelligence. It may help you overcome some of the effects of aging or ADD, but mostly, it's fun. Operating System: Windows, Linux.

21. Open Sonic

Yes, there's now an open-source version of Sonic the hedgehog. While it is different from the other Sonic games, it should be familiar. Unfortunately, the alpha release has only two levels so far, and the OS X version isn't very polished. Operating System: Windows, Linux, OS X.

Mind Mapping

22. XMind

Winner of multiple awards, XMind is a brainstorming and mind mapping application that is similar to (and compatible with) FreeMind. Originally released under a commercial license, it went open-source about a year ago. The latest release includes Web 2.0 and Gantt project tracking features. Operating System: Windows, Linux, OS X.

Mobile Applications

23. winPenPack

This app lets you take your favorite open-source apps with you wherever you go on a USB thumb drive. It's similar to the better known PortableApps.com, but it includes a lot more software. It comes in six different flavors: 2Gb, Essential, Game, School, Web, and Personal. Operating System: Windows.

Multimedia Tools

24. MP4Creator

Part of Cisco's mpeg4ip suite, MP4Creator lets you create and modify MP4 files. With it you can turn existing audio and video files into streams that can be understood by most devices, including PCs, iPods, iPhones, and others. Operating System: Windows.

25. Streamy

This media recorder allows you to watch (or listen to) streaming video or audio, download files, and drag and drop files to play on your computer or iPod. The handy bookmark manager makes it possible to keep track of your favorite sites. Operating System: Windows, Linux, OS X.

Novel Writing

26. Storybook

Although it's designed primarily for novelists, Storybook helps creative writers of all kinds keep track of characters, locations, and multiple plot lines. Track plot lines chronologically, organize chapters and scenes, type your manuscript, and more. Operating System: OS Independent.

Operating System

27. Easy Peasy

Don't like the operating system that shipped with your netbook? Try Easy Peasy instead. It's based on Ubuntu and is optimized for use on the Asus eee. Operating System: Linux.

28. eeebuntu

As you can probably tell from the name, eeebuntu is another Ubuntu-based operating system for the eee netbook. It includes a variety of popular open-source applications, like Firefox, OpenOffice.org, Pidgin, Thunderbird, VLC, Banshee, and more. Operating System: Linux.

29. andLinux

Want to give Linux a try without giving up your Windows machine? Or do you want to use an app that only works in Linux? andLinux lets Windows users take the Ubuntu desktop for a spin and run most Linux applications. Operating System: Windows.

30. Portable Ubuntu Remix

Similar to andLinux, Portable Ubuntu Remix lets you run Linux apps in Windows. It's not quite as polished as andLinux, but some people prefer it. Operating System: Windows.

31. Moblin

Now managed by the Linux Foundation, Moblin was originally developed by Intel as a Linux-based operating system for netbooks and other mobile devices. Specifically, it was designed to run (and sell) the Intel Atom processors released in April 2008. Operating System: Linux.

32. Tiny Core Linux

The name says it all - Tiny Core Linux squeezes a desktop Linux into just 10MB. To really use the OS, though, you'll probably have to add extensions, but the app gives you complete control over which extensions you add. You end up with a lightweight, customized Linux distribution. Operating System: Linux.

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