Projects for which the source code is distributed under one of the many open source licences. Open source projects may be used and shared freely but typically you must distribute the software under same terms.
Logfilter is a simple command line log file filter tool for Apache web server. The project is now dead though the source code is still hosted at Google Code for those who are interested. Please feel free to fork.
TimeTag is an open source time series database implemented from the ground up for Windows PowerShell. If you want to know more about TimeTag, please visit the dedicated TimeTag project website.