ninebob said:
Igorian, your link requires you to log in or register to continue, and I'm not going to register to a site I know nothing about.
You have to register because you need to be logged in to a SIP server for it to work (They have to know where to route your calls). I have used this site and can assure you there is nothing sinister and it's entirely free to receive calls and pay as you go if you want to make call through the PSTN system or free to other VOIP users. Basically, when you log on to the net, a small client logs on to the remote server (Sipgate in this case) and registers your PC as ready to make calls. When you register, you can opt for a geographic telephone number 020, 01604 etc or a non geographic 0845 or 0870. Everthing else then works like a normal phone, obviously using your PC.
There are various options if you want to use a phone. One is to buy a dedicated Internet phone, which connects via an adaptor to your phone line and uses the broadband connection rather than the analogue one. I've not used one of these, but searching on Internet Phone in Google will bring up lots of results.
I replaced my broadband router with one that offers VOIP and a normal phone plugs directly into this. You then sign up to Sipgate, draytel or one of the many others and use the phone as normal. The router I use is a
Draytek Vigor2600VGi, which has a lot of features and is a little pricey, but there are cheaper models. In addition to the telephone number, you get a Session Initiation Protocol (SIP) address, which allows other VOIP users to call you for free. It also means I don't have to have the PC on to receive calls, just the router.