In the August S&T there is an article on a trackball telescope. The author states that he is unaware of anyone else having come-up with the idea, but I am positive I have seen the concept prototyped and published somewhere else. I doubt it was S&T, as they should have caught that; it was probably ATM Journal or AA (the Tom Clark publication). I think the prior inventor did it with 4" or 6" optics. Can anyone help me pin it down? I'll try and dig out my old ATM journal issues in the next few days. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com