I would recommend that each one contribute with his peace of Mac-Art, either done on a Mac or done about a Mac. I wanna see this Photoshop masters at work, ah!
Me? I'm into 3D, as soon as I'll install Rhino into my Windows partition I'll be contributing as well...
Illustrator geniuses, don't be shy now! Let me see what you can do with all that hardware and the dad's money you spent on it!