GeoJackal is a fast, light-weight database for geocaches. It is currently in alpha stadium.
- Import from geocaching.com
- geocaches are stored in a SQLite database
- map view with tiles from OpenStreetMap
- currently runs on Linux, Windows 2000/XP/Vista/7, and Windows Mobile 5/6.
TODO: add some screenshots
All you need for developing is on SourceForge.