Saw this over at Cloudynights and thought i would post it here for you guys to see. Its a very neat idea on using gravity for tracking. Based on the principles of Poncet table/equatorial platform.
Discussion on Cloudynights.
http://www.cloudynights.com/ubbthrea.../o/all/fpart/1
The project website.
http://subarcsec.com/index.html
What i really like is the use of natural forces to avoid the use of battery power.
Regards
Netwolf.