Don't know what it's like in the UK but CAT5 or CAT6 ethernet cables are so cheap here (20 metres for €15 at the nearest Auchan supermarket) and so easy to lay
Agree. Install a wall socket, then into the wall, up the cavity, through the upstairs floor, further up to the top ceiling, then down the wall to another wall socket. Easy.
There's a few on drugs here, methinks...