Wireless focus for the Ronin-M
Depends on the type of mount your camera has. This is a good solution for the A7S or A7R and was recently shown at NAB: The Aputure DEC. They also have one for MFT.

http://www.bhphotovideo.com/c/search?ci=23192&amp;N=3989452947&amp;mnp=0&amp;mxp=1000

And this should be available soon!

https://www.kickstarter.com/projects/1608311032/lenzhound-wireless-lens-motor-control-system/