Moves is an app to track your mobile phone location 24/7. I have had it running for a good while now on my iPhone. The tracked data can be exported via the Export service, and I wrote a Processing application to visualize that on some map tiles.
This is an ongoing investigation of the land use patterns of my homeland, Finland.
Finland is a country with a huge variability in the land use patterns within administrative municipalities (cf. LocalFinland.fi for background information). The major towns are packed with infrastructural and residential areas filled with productive economical activities, whereas the administrative burden of the northern municipalities extend over large, practically uninhabitated areas of forests, and only a small portion of the administrative area is affected by economically active infrastructure.
Now something different.
Off-piste snowboarding in urban or rural areas is a time-consuming hobby especially outside the mountain areas, because the best spots are neither marked nor listed in city maps. A lazy snowboarder wants to find a nice, open hillside with decent slope and sparse treeline, but finding even a few spots requires numerous trips to countless would-be locations. But hey, we have open source GIS tools and Open Data to mine for just that!
So I opened up Quantum GIS and the Raster Calculator.