I'm a creative professional. I do most of my work on an iPad 2 during the day. I use Adobe Proto and Photoshop on it, OmniGraffle, Coda Lite, and Apple Pages and Numbers. When I get home, I get my files from Dropbox/Adobe.com/iWork.com, and use my 2004 PowerBook G4 to turn it into an InDesign document, if it hasn't been published on the web already.

I also have a recent Mac mini, but even though it's the beefiest machine that I own, I only use it to view movies.