Oh sure, you can run Linux apps on the Linux desktop. Obviously. But Linux developers aren't content to stay confined. As a sign of Linux's ever expanding influence, the Windows desktop also has an sprawling menu of open source apps. The following list is a mix of applications for home, business and education users from a broad range of categories.
With the end of life for Windows XP approaching, many Windows users may be looking particularly for software that runs on Windows 7 or Windows 8. To meet their needs, we've noted which versions of Windows each application supports, where possible. (Note that not all of the open source applications on the list specify with versions of Windows are supported.)
Some of the applications on the list run on Windows only, but others also run on Linux or OS X.
As always, if you think we should have included other open source applications in our list, please feel free to note them in the comments section below.
If you're a Windows user with no previous open source experience, OpenDisc is a good place to start. It's a collection of many of the most popular open source applications for Windows, including Blender, the Gimp, Scribus, Firefox, Thunderbird, Audacity, Celestia, VLC, LibreOffice and many more. Operating System: Windows
This open source Windows app collection is portable, meaning you can install it on a thumb drive or a cloud service so that you can use your favorite apps from any system. In addition to the collection, the site also features portable versions more than 300 other open source and freeware apps. Operating System: Windows (8, 7, Vista and XP)
Similar to PortableApps.com, winPenPack is a collection of open source applications that can be installed and run from a thumb drive. It comes in two pre-configured versions—Essential and Full—as well as a Personal version that users can customize themselves. Operating System: Windows.
Used by more than 600,000 people, ClamWin is based on the popular Clam AV antivirus engine used by many Linux users. It integrates with Windows Explorer and Microsoft Outlook. Users should note that it requires manual scanning of files in order to detect malware; in other words, you have to click on a file in order to scan it. Operating System: Windows (8, 7, Vista, XP, Me, 2000, 98, Server 2012, Server 2008, Server 2003)
Popular with science teachers and space buffs of all ages, Celestia allows users to see the night skies as they would appear from any point in the known universe, at any point in time. The project's main website has been down recently. The link above will take you to the Sourceforge page, and you can also find information and add-ons at the Celestia Motherlode website. Operating System: Windows, Linux, OS X
The brains behind many planetarium displays, Stellarium shows the night skies as they appear to the naked eye from points on earth. The default installation includes more than 600,000 stars, but you can also add other catalogs that include more than 210 million stars. Operating System: Windows (32- and 64-bit), Linux, OS X.
An alternative to iTunes, Amarok aims to make it easy to discover and listen to your favorite music. It boasts an attractive, easy-to-use interface and integration with a wide variety of Web-based music services. Operating System: Windows (8, 7, Vista, XP), Linux, OS X, iOS
For the Linux community, Audacity has long been the go-to tool for recording and editing audio. Although not intended for use by professional recording studios, it has all the features home users and hobbyists are likely to need or want. Operating System: Windows (7, 8, Vista, XP, 2000), Linux, OS X
Based on the same code as Amarok, Clementine developers have focused on creating a fast, easy-to-use interface for this audio player. The latest version also includes the ability to control it remotely with an Android phone. Operating System: Windows (8, 7, Vista, XP), Linux, OS X, Android
If you're a musician, there's no need to spend tons of money on an application to print sheet music. Easy-to-use Musescore prints beautifully, and it's completely free. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
The Advanced Maryland Automatic Network Disk Archiver, a.k.a. AMANDA, claims to be the most popular open source backup software in the world. Aimed at organizations, it backs up networks, not standalone machines. Zmanda, which sponsors the project, offers a cloud-based solution based on the same code. Operating System: Windows (7, Vista, XP Pro, Server 2008, Server 2003), Linux, OS X
12. Areca Backup
Made for home users, Areca backs up standalone systems. It's highly versatile and offers compression, encryption, and support for most storage media. Operating System: Windows, Linux
Downloaded more than 750,000 times, Redo aims to make backup and recovery very easy for home users. It claims to be able to do bare metal restores in as little as ten minutes. Operating System: Windows, Linux
Immensely popular, WordPress runs more than 60 million websites and blogs. The code at this site will allow you to set up your own server, or you can use the free hosted service at WordPress.com Operating System: Windows (8, 7, Vista, XP, Server 2012, Server 2008 R2, Server 2008, Server 2003), Linux, OS X, iOS, Android, BlackBerry, Windows Phone, others
This is the open source project that provides the basis for the Chrome browser. It aims to be safer, faster and more stable than other browsers. Operating System: Windows (8, 7), Linux, OS X, Chrome OS, iOS, Android
One of the most widely used open source applications, Mozilla's Firefox browser offers advanced performance, security and customization capabilities. Key features include the awesome bar, a pinnable tabbed interface, synchronization, integrated search and more. Operating System: Windows (8, 7, Vista, XP, Server 2003), Linux, OS X, Android
17. Tor Browser
If you're worried that people might be spying on your Internet usage—or if you are a spy and don't want people to know what you're up to—Tor offers anonymous Web browsing. It makes communications untraceable by bouncing them around a network of secure servers and relays. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
Under development since 1979, BRL-CAD is a package of more than 400 tools, utilities and applications for creating 2D and 3D solid geometry models. Its best-known user is the U.S. military. Operating System: Windows, Linux, OS X, others
Track projects, milestones and tasks for group projects in the cloud with Collabtive. It's very similar to Basecamp and will even import Basecamp data. Operating System: OS Independent
20. Feng Office
Built to offer project management for professional services organizations, Feng Office boasts more than 1 million users in more than 150 different countries. In addition to the free download, it also comes in cloud-based or paid on-site versions. Operating System: Windows, Linux, OS X
PeaZip supports more than 150 different archive file formats, including some that offer very tight compression. It can also convert, split, encrypt or securely delete compressed files. Operating System: Windows (8, 7, Vista, NT, XP, 2000, 9x), Linux, OS X.
Used by companies like Bank of America, BP, Hilton, Samsung and Kaiser Permamente, DNN is one of the most popular open source Web platforms for business. Paid and free versions are available. Operating System: Windows (8, 7, Vista, Server 2008, Server 2012)
Drupal boasts a community of more than 1 million people from 230 different countries. Extremely popular, its users include AOL, Harvard, MIT, San Jose State University, MTV, Sony Music and many others. Operating System: OS Independent
Downloaded more than 35 million times, Joomla runs millions of websites, including those of Ebay, Barnes & Noble, GE and Ikea. It's won numerous awards and has a very active community of users. Operating System: OS Independent
Plone claims to be "among the top 2% of all open source projects worldwide," as far as the size of its development team and user base. Its goal is to create websites that are fast, powerful and beautiful. Operating System: Windows, Linux, OS X
Millions of people around the world use the Sugar CRM platform. Organizations can host the free version of the software themselves or use one of the cloud-based paid editions. Operating System: OS Independent