
I started using my wife's 12" Apple iBook, so I could be close to the scope. Then I used my gorgeous 15" Apple Powerbook running OSX Panther for imaging, and an old Fjitsu Lifebook 675 running Windows 2000 Pro for scope control and auto-guiding.
The Powerbook and the Lifebook have now been replaced, and I'm currently using a MacBook Pro which can run either OSX or Windows Xp Pro! Superb!
Now I can run all the great astro software out there on my Mac :)
I do however still have a Dell Latitude CS PC notebook too, which is used sometimes.