I have a telescope my grandad bought in 1952 for £50 (about £750/$1300 today!) and although it's only a brass 3" refractor you can *just* see the ice caps on Mars and the rings of Saturn. I haven't been out to look at Saturn recently but really must do so.

A good site for easy calculation of relvant data is http://www.heavens-above.com/ - I mainly use it for calculating Iridium flares which are very impressive if you haven't seen one (make sure the first one you see is a -6/7 - bring your sunglasses!)

Gareth