Didstopia has announced Fokus for Mac OS X. The US$4.99 app is designed to keep you focused on your current task by dimming all other windows except the currently active one.
The folks at Didstopia says this helps to reduce eye strain and headaches. Fokus also lets you choose the best brightness for background windows. The software works with most applications and windows.
Fokus 1.0.0 is available worldwide through the Fokus website (http://didstopia.com) and through Didstopia Shop. It requires Mac OS X 10.9 or higher.