Note: I have very little clue about electricity/circuits so I can only provide info on what I know.
The setup: In our upstairs bedroom we have two wall sockets on either side of the room, with two 3-pin plugs on each (UK Connectors). For the last couple of years we have had one desktop PC & monitor setup on one socket and a PC/dual monitor, Two-Routers, Media Server, Home Theatre PC and TV set up on the other side of the room.
The problem: The power stopped working for the socket powering the Routers/TV/PC/etc. We got an electrician in who couldn't find anything wrong with the fuse box or the sockets (we found there's another socket also on the same circuit not working). He said we would have to start pulling up the floorboards to find a junction box and at the moment, we really don't want to start doing something like that.
What we want to do: Buy an extension cord (most likely 8m/10m) to route around the room to provide power to the PC and Routers from the socket currently functioning. My worry, and this is a huge worry, is that if we run an extension cord from this socket we will have too much running on the single circuit with two computers, three monitors, two internet routers at minimum...
Is this dangerous? I know you're not supposed to use extension cords permanently but we don't want to be ripping up carpets until we move out in a year/two years, when it makes more sense. But, if using an extension cord in this situation is likely to overload the working circuit or worse, set on fire, it ain't good.