Mine is a bit of an obscure but cheap alternative to the
mainstream. It's made of polystyrene foam triangles and is
a geodesic hemisphere. Copied from a brilliant DIY step by step
guide written by the designer Joe Garlitz. There are dozens
of Joe's design around the world now and quite a few in Australia.
Mine started out originally with a skin of a hybrid type of
papier-mache (don't laugh) , which lasted about 6 years then
I re-skinned it with a concrete render. It sits on a 3 ft colourbond
wall and the scope is fully remote controlled.
It has also moved sideways a few metres so I could build a pool!
Made in 2000 and survived quite a few wild storms so far
A few construction details here if anyone is interested:
http://jfbo.webs.com/observatory.htm
http://jfbo.webs.com/domeconstructionpage4.htm
Steve