Lina

With LINA, applications written for Linux run on Windows, Mac OS X and UNIX operating systems. LINA is a thin virtual layer that enables developers to write and compile code using ordinary Linux tools, then run that code on a variety of operating systems. For users, LINA runs invisibly in the background, enabling them to install and run these Linux applications as if they were native to that users' operating system.

http://www.openlina.com/download.html

Baku

Baku allows you to search for system registry errors and unneeded files that can be safely removed.

http://pmcchp.com/baku/index.html