Project Space
One thing I'd really love to use is some system that could encapsulate a project, including all of its files, software and running state. I have a bunch of different projects that I work on at different times, and keeping track of all the windows for each of them is a constant struggle.
Ideally, it'd be something kind of like a lightweight VM. You open up all your code editors, tools, browser windows, running services and so on, arrange them however you like, and then save that configuration as a Project Space. Then, when you're done working on it, you can close the space and everything goes away. When you want it back you can open it again and everything resumes just as it was.
I'm currently using Mac OS X's Mission Control and, as of this writing, have about 15 virtual desktops, almost all of them for project windows. With something like Project Space I could get that number much closer to zero and maybe not seem like so much of a hoarder.