The Velbus home automation system is manufactured by Velleman NV, a Belgium electronics company. It is easy to use and comprises of several modules which fit on to standard DIN rail.
Modules range from dimmers, switches (relays), motor control and temperature sensors. It is easy to program using a PC or Laptop. Full specifications and applications can be found at:
http://www.esr.co.uk/velleman/products/index_velbus.htm
I believe this is the only UK distributor stocking the product.