Yuk! Here we have a number of choices somewhat sullied by the fact that one has to pay line rental to BT as a penance for having an Internet connection. A levy is also made against part of the payment made to the ISP used so it's very much a case of pay twice. However calls between VOIP units are free. Modem costs are minimal and any old PC can be used as a PBX unit and made to do all sorts of 'interesting' things.
Very true. Very much a case of mobile to the fore and hope the power outage is local.
I can run all of these systems from the 'old' PC used as my server. I especially like having lots of telephone numbers which can be directed to specific handsets or extensions
Cheers.