Hi all,
if you're searching for a free (and open) logging software you might consider Observation Manager (
http://observation.sourceforge.net/).
It's written in Java, so it should run on almost all platforms.
Data is stored in a free and open dataformat (XML Format) called COMAST. This ensures your data is compatible with other software and you're able to exchange data with e.g. friends. (A WebApplication with import/export capabilities with currently in the making:
http://www.deepskylog.org/deepsky/)
Feedback is for sure welcome!
Hope you like it...
Dirk