Blackbox for Windows is an alternative shell for Microsoft Windows. It is based stylistically on the Blackbox window manager for the X Window System, however it does not use the same codebase except for the gradient rendering code.
Still use it. Even under Windows 8. Unprecedented configurability and weightlessness on resources gives it my choice over any other windows shell.
Although I currently don't use Blackbox anymore, I have been using it (a few years bb4win, and a few bbLean branch) for years...