Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I only use it when I get a research test (once a month max). It only allows me to do it on Windows as the video stream doesn't work with Flip4Mac. So I just breakout hubby's PC laptop.
 
Simply because

It works well with the vast amount of PC hardware/devices of choice that I have.

I really make use of the fact that I can get reliable Microsoft tested and certified drivers for all my devices without spending a single minute.

My main workstation is a self built one - not only for the reason that it works out cheaper but also for the fact that I can choose what goes in it. And Vista x64 works perfectly fine on this quad core box.

I use Linux on my headless mac mini server because most development software that I use requires Linux/Windows/Solaris. I am also more comfortable with Linux and it just works.

Mac OS X is on both my and my wife's laptops (Macbook Pro and Macbook).

So in short OSX for everything desktop, Windows for Workstation and Linux for Server - right tool for the job! 🙂
 
I use windows for everyday movie watching etc. I've realized that all the tiger features are in Xp... they're just hiding.
 
2 Windows-only Apps

😎
MS Visio...nothing remotely as good on a mac

MS Project....dittio....and an industry standard.


😎
 
Because I choose to?

My fastest computer is a PC.

I do have Tiger running on it on the side, but still. 😛

I mainly play games. Which explains a ton.
 
Because I'm an Iconoclastic Luddite who is resistant to change of any kind. 😛

Actually, I'm lying.
I have yet to find any really good reason to run Windows at all.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.