Gerber came out with this nifty gadget with quite a few nifty tools for AR maintenance. It fits in to Magpul MIAD and MOE grips and weighs 2.8oz.
https://www.youtube.com/watch?v=6BAZYCA9QGU
Website: http://www.gerbergear.com/Tactical/Tools/Short-Stack_31-002997
Price is $50
From: Gerber