I like the idea of the visibility of an open source tool.
Psystar uses open source tools designed to work around the issue.
Active Agenda is an open source risk management tool.
Verilator is an open source tool, and has in turn been adopted by a number of other projects.
Agrega is being developed with well known open source tools.
Cych has compiled a list of open source 3D-modelling tools for use in education.
It is in open source tools all over the world.
The ability to run on freely available, open source tools.
They use open source tools and lean management methods to improve their productivity.
A common recommendation is to use open source security tools where possible, since they allow independent checks on the quality of the methods used.