This company is local to me, and the missus is looking to perhaps apply as a software engineer - I'd never heard of them:
http://www.helitrak.com
They appear to have a single product only recently introduced and not yet ready for prime time, which is aimed rather squarely at the R-22 (initially). This device is an automatic reaction to the low rotor RPM warning in the Robbie, literally yanking the collective down to re-establish rotor RPM.
It's a brilliantly simple package from all appearances and seems to address a common low-inertia problem. What I don't know yet is whether it offers a graduated response (lowering the collective only enough to satisfy RPM requirements, or if it simply slams the collective to the stops) nor how quickly it releases the collective back to the pilot's control.
It's a bit more than a stick shaker, obviously. On first blush it seems like a great idea... but depending on the operating parameters it also sounds like a potential fright.
I'm curious as to the opinions of the group.
Disclaimer: I have no ties to nor interest in the company in question and am only interested in the device as it pertains to helo safety. Unless the missus ends up working there at some point, anyway...