TuxFamily provides free hosting to any site with a recognized open source license. At last count, it had more than 2,300 projects. Note that this is a French organization, so it is sometimes difficult to find English translations for parts of the site.
Home to just over 250 projects, KnowledgeForge is one of the smaller open source hosting sites. It's supported by the Open Knowledge Foundation and works with multiple version control systems.
Short for "Open Source Observatory and Repository," OSOR is a European Union site for open source projects that can be used in public administrations. It currently hosts more than 200 projects and links to nearly 2,500 more, and the site also contains helpful research and news related to free and open source software.
Formerly known as "the ObjectWeb Forge," OW2 provides hosting for open source projects related to infrastructure software. It currently hosts 188 projects.
Owned by the same company that owns SourceForge, Freshmeat boasts "the Web's largest index of Unix and cross-platform software." Note that while most of the applications listed on the site are open source, not all of them are.
Recently purchased by Black Duck Software, Ohloh is an openly-edited directory of open source projects. It provides a variety of general information about each project (language, license, Web site, etc.), as well as user ratings, downloads, and some interesting tools that can help you compare various projects.
This site aims to provide end users with open source alternatives to well-known commercial software. This directory isn't as exhaustive as some, but the way it's formatted makes it easily accessible by open source newbies.
Sponsored by GigaOm, this site provides information and ratings about more than 150,000 open source projects. It includes a helpful "alternatives" tab, which makes it easy to find and compare similar open source projects.
25. OS Living
This site aims to collect "the Web's best open source software" in its archive. In addition to a keyword search tool, it also allows users to search by category, making it easy to find the type of software you're looking for.
This site is maintained by the Free Software Foundation (the owners of the GNU project) and United Nations Education, Scientific and Cultural Organization (UNESCO). In addition to a large library of software links, it also includes a lot of information about the philosophy behind open source software.
Like several others in this category, this site also attempts to filter out the "best" of open source software. It doesn't provide a lot of data about each applicationinstead it primarily provides ratings and links to the project's Web sites.
Webi offers a basic listing of open source software with links to downloads. It's heavy on games, which have their own section of the site.
29. The LOOP List
The Ubuntu site includes this helpful list of open source software that runs on Windows. It can be edited by anyone, but it's limited to the three "best" open source applications for any given category.
This UK-based site offers links to open source projects that are helpful for educators. This directory is a little bit more difficult to read and search than some of the others but is still helpful.