I'm not picking, I am responding to your odd statement. I know there are some dedicated programs for Windoze, but most bizness apps are ported to Macs, as well.
What caught my eye, though, was your allegiance to the Thinkpad, and then your intention to buy a new PowerBook...
What programs do you use, that are so proprietary?
We've several thousand programmers working around the world to develop the "proprietary" software that drives our business. You can't do everything with Hypercard and Excel, eh?