A Flash Meter with Cactus Transmitter
would be nice.
I understand some flash meters have a sync contact which you could connect to a V6 (or V5) in order to set off flashes you want to meter.
I agree that a single device integrating the two functions would be cool, though.
edited May 2015
It could be four functions actually. Setting the flashes, fire the flashes for measurement, measure the result and it could even release the camera with another V6 as receiver on top.
Would be a great tool for incident light metering where you place your light meter in from of the cam and the flashes.
It would be a good idea.