Application servers - Java Apache, JBoss, PHP, Zope open source projects - pleas visit this link to lear more.
Databases - MySQL, Postgres, GNU SQL, InterBase open source projects - pleas visit this link to lear more.
Editors - Archy, Emacs, Java open source projects - pleas visit this link to lear more.
Graphics - OpenGL, The GIMP open source projects - pleas visit this link to lear more.
Internet - Clients, Servers, Web Applications open source projects rewiev - pleas visit this link to lear more.
Office Suites - OpenOffice.org, StarOffice open source projects - pleas visit this link to lear more.
Operating Systems - Fedora, Slackware, Suse, MEPIS, Mandriva and other distributions - pleas visit this link to lear more.