Should have mentioned it before. Having given Google Talk a go, I can report that it appears to Just Work™. No messing about with firewalls and routers. Since I had a GMail account already there was no fiddly registration process. And the sound quality is good. I'd also recommend the Plantronics headset that I got, although at the price (almost £30, I think) I wouldn't have expected anything less. If you want to try it out, give me a call. Help me recoup my headset investment with free phone calls! (Mind you, I think I've gotten my money's worth already. :D ) I've got Skype too, but that was a bit flakey for me before and I have no contacts now. If you're on my friends list already (and I figure you must be to be bothering to read this) then you can find my contact details in another post. If not, just leave a comment or bug me in real life and I'll let you know.
Sorry for clogging up all of your friends pages. I just seem to have a lot to say at the moment. I'm sure it won't last.