...was a module junction box that significantly improves module safety by using a high frequency signal from the inverter to say when to provide power to the inverter.  Called the Coolbox, I can't wait for it to be available here.  RES is developing this needed system component. 

A potential problem here in California is that fire departments do not like power sources that they cannot disconnect in case of fire. Unless it is dark out, it is really difficult to bring one of my systems to a zero voltage state.  Unlike grid power that the fire department can disconnect with one arm while holding a firehose with the other [the "five finger" rule], my systems are energized as long as the sun is up.

The Coolbox short circuits a module's positive and negative poles using a transistor.  This continues until the inverter tells it to send power by a separate high-frequency signal, forcing the transistor to switch to a non-conducting state, thereby applying module voltage across the poles.

Sometimes it is the little things that make a big difference.