I love far too many different things, so I never finish anything. But some things have nevertheless reached stages that are useful, or at least interesting to people, and they are listed here.
Active and updated
Radio Archive - an archive of music radio programs; it is active and updated every week (with some delays). Kirill, aka Deadbook, and I work on it together.
OpenStreetMaps - I improve and expand free maps created on the same principle as Wikipedia.
Cycling Map - a heat map of my bike rides through 2015 (the ones recorded with trackers), excluding training rides