Saw this on Cloudy Nights:
http://www.ebay.com/itm/41-Ritchey-C...item35e5f30949
For the truly serious astrophotographer!
Here is the Cloudy Nights link, it was commissioned by a member there who later died in an accident. Full mirror tech details are in this thread:
http://www.cloudynights.com/topic/49.../#entry6472835