I have been running Vista full time for a little over two months now and even with all the big new features and functionality in Vista, I am amazed at all the little things that have been "fixed.
For as long as I could remember, I always install my OS on the C partition and create another partition for my data. Once the OS was installed I'd go in and redirect a lot of folders to the other partition. That way if I ever needed to re-install, I could blow away C and not lose my data. It was pretty easy to do in XP, but Vista makes it even easier. I discovered this one by accident but once Vista is installed, browse to C:\Users\YourUsername and select all the folders and then cut and paste them to the other partition. Vista will update all the mappings automatically!
So what little thing have yuo found in Vista that makes your life easier? If you want to share post it as a comment!