Some neat projects exist on codeplex.com that relate to sharepoint

FAST Search Query Analyzer: http://fastforsharepoint.codeplex.com/

Sharepoint content Migration tool: http://spdeploymentwizard.codeplex.com/

Sharepoint Feature Administration and Clean Up Tool: http://featureadmin.codeplex.com/

Sharepoint Farm Report: http://spsfarmreport.codeplex.com/ (an .exe – somewhat jumbled html output)

Sharepoint 2010 Farm Poster http://spposter.codeplex.com/ (some nice Powershell scripts)