Extending telephone line over mains!?

["noel_pilot" <HA@xxxxxxxxxxxxxxxxxx>]

Hey all,
Horrible question here, a friend is only on dialup and we need to get
a phone line to her office, no way of feasibly running a cable,
im sure i remember some products way back when that you plugged a box
into a mains socket one by the phone csocket one by the pc and it
extnded it over the mains.
Can't for the life of me remember what they called and having a blonde
moment with what to search google for!!

any ideas?!?!

thanks

Noel