I have made a donation to the open source GIS program QGIS. http://qgis.org/en/sponsorship/donors.html
GIS is a key enabler for understanding so much of our world and life, and I can distinctly recall my frustration in the late 90's when GIS investments were the only technology specifically excluded to community-based environment organisations. In fact, I threw the application booklet across the room at the time.
This is a more positive response.