This is a collection of various open source tools:
StExBar: The ultimate extensions for Windows Explorer or: what Microsoft forgot to implement in the explorer.
SKTimeStamp: Adds a new page to the Windows explorer properties where you can manipulate file times
AAClr: change Aero colors to match the wallpaper
FileTool: a small utility to create files with random data for testing
tabspace: a command line tool to change all tabs/spaces to tabs/spaces and vice versa in text/code...