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Hi all,

I am in the process of buying a bungalow, and want to install two or more
Cat5 ports into each room (and no, wireless ethernet alone won't do
because I want to run A/V over it - see avnex.co.uk - as well as POTS and
ethernet).

What's the best way of getting the Cat5 into the walls? I can get into the
ceiling easily enough. Any ideas? Best to just run the cable down the wall
and ignore it? Dig a narrow channel (not all the way through the board)
into the plasterboard and plaster over it? Suggestions?

Run as much as you can under floorboards or through the roof space,
then up or down inside the wall to the sockets - you'll probably have
to hack out a bit of plasterboard top and bottom so you can get
behind it, and over any noggins that get in the way (you can groove
the noggin to run the cable past it) then make good afterwards.
Remember not to run the Cat5 close and parallel to any power cables,
and avoid fluorescent fittings too. While you're doing it you might
as well fit more runs of Cat5 than you think you'll need, and always
leave some extra length in the cavity in case you need to replace
sockets at some point.