OpenStreetMap
I always loved the idea behind OpenStreetMap. Mostly because of my open source experience and sites Wikipedia, these show that with enough people doing a little bit of work in the area they know, it is possible to create results which are better and more free than the conventional commercial offerings.
rest on: http://christof.damian.net/2009/09/new-hobby-openstreetmapping.html
Discussion
Comment from datalogg on 27 September 2009 at 15:14
I liked the observation that Openstreetmap hits the sweet spot between cycling, gadgetry, geeking out, and helping the community. That's why it's my new best thing ever, too ;-)