http://www.partitionwizard.com/free-partition-manager.html

I’d used the built in partition manager in the Windows 7 Disk Management tools to shrink my primary volume and make the second drive, but then I realised I’d made it too big and needed a couple of extra gig added back onto my C drive. The only way I could see to do that using Windows would have been to copy all the files from D to C, delete D, expand C and create a new D in the remaining space! :(

Partition Wizard 5 let me just shrink D, move D along into the blank space and then expand C. The interface is very much like that of good ol’ Powerquest’s Partition Magic which makes it very easy to get comfortable with.

The home edition of the software is completely free, it works with Windows 7 64-bit, and it took about 2 and a half mintues finish the job! :)

(By the way, I’m not at all affiliated with this software or it’s author, I just found it on Google and thought it was really good! ;))