I recently got a mac mini and decided to give bootcamp a try as I needed a native windows machine from time to time. I initially created a 10GB bootcamp partition, thinking that would be enough, but after installing Visual Studio and a load of other stuff I was soon down to about 200mb. I had been fooled by the bootcamp setup into thinking that it would allow me to resize the partition later, but it doesn’t – the only choice you have is to delete the partition and start again. I didn’t want to install windows yet again, so after googling around I found an excellent bit of free software called WinClone. This allowed me to create an image of the bootcamp partition from within OSX, then delete the bootcamp partition, create a new one – (20gb this time) and restore the windows image. The added bonus is that I now have a backup of the windows install, should I ever stuff it up.