Linux installation bus (Score 1)

This hotel uses some sort of self made installation bus, controlled by Linux

I wonder why there are no or few such applications like a "linux controlled" house or something...

by "linux controlled" i mean elictrically e.g. a lightswitch is connected via ethernet or some sort of installation bus to the linuxbox, and the box decides what to do... e.g. turn the light on (also via some sort of network device)...

There is some sort of bus called InstaBUS from Simens, but i have not seen any adapter for PCs..

a adapter for serial would be fine, anyone??

and then lets write a neat proggy in perl or something. :)