One for the tech heads...
 

Just sorting some broadband out,at the moment,my main telephone point is downstairs and i'm running an extension cable out of that,to my pc upstairs.Am i going to be able to put a microfilter onto the phone point,then put a double adapter socket onto the filter,which will then have the phone plugged into one socket and the extension into the other,then another filter upstairs which i plug the new modem into ???.All this elastictrickery and techmology is too much,we've only just got running water down here...moggers@mybrainhurts.com

You only need the filter for the phone not the broadband modem. Most filters have two outputs, one for the phone (filtered) and one for the broadband modem (unfiltered).

Ideally you should run the extension upstairs, directly from the line downstairs before the microfilter and have microfilters both upstairs and downstairs.

If you don't want a phone upstairs, you could run the upstairs link from the downstairs ADSL outlet on the microfilter and you wouldn't need to filter upstairs.

for the second option you would need a long RJ11 to run from the downstairs filter to to router upstairs.