Something I have been thinking that could drastically reduce the cost of powerline devices in a bridge that uses the switching circuit to provide both regulation and data.
Basically you could have a wifi, bluetooth, homeplug 230Vac low voltage bridge. This would allow a simple 16 device master/slave 12v DC side for sensors and devices with extremely simple low cost powerline data embedded and created by the already existing SMPS circuitry.
The cost saving on end points could be huge as a very simple data line of a strong signal could be used and multiplexed into power usage.
Would be prefect form for LED lighting to home control systems.