PIC through live wire communication

Hi,
Does any one know where I can find information/circuit diagrams about setting up 2 pic chips to send and recieve data using an existing power line?? (communication modem)

well, i saw something on the net, but it was for audio signa, but you can use like you said a something like a modem to convert from digital to analog and viceversa.
ffrom what i remember you need about 4 transformers of some special type.
search the net and you will find some things.
whatever i have is for unidirectional comunication.

S*T Microelec*tronics have power line modem.

why do you write like that?
yes, there are some sort of comunication devices, even used by computers, but i know there are quite expensive.