Eclipse Open Source IDE mostly for Java.

SharpDevelop Open Source IDE for developing .NET projects #develop (short for SharpDevelop) is a free IDE for C#, VB.NET and Boo projects on Microsoft’s .NET platform.

TortoiseCvs.Org Integrating CVS (Code version System) into Windows explorer windows.

SubVersion Subversion is meant to be a better CVS, so it has most of CVS’s features.
Directories, renames, and file meta-data are versioned.
Lack of these features is one of the most common complaints against CVS. Subversion versions not only file contents and file existence, but also directories, copies, and renames. It also allows arbitrary metadata (“properties”) to be versioned along with any file or directory, and provides a mechanism for versioning the `execute’ permission flag on files.

ConTEXT Programmers editor showing highlighting in almost all major languages

PuTTY Open Source Terminal Emulator 0.60 binaries 1.44mb(for windows) 0.60 Windows Source 1.25mb