Finally a viable alternative to Skype.. http://www.gizmoproject.com/. There’s probably ton’s of VOIP clients but Skype and Gizmo seem like the only two to be aimed at the home user. I use SkypeOut all the time to call home to Ireland and now hopefully with some competition, the prices will drop even further.
I got a USB -> RJ11 Adaptor on ebay (http://www.yamamoto-group.co.uk/index.php?page=easyblue) which lets me use SkypeOut with my regular cordless phone. I also receive Skype calls on my phone too (I’ve only received one though 🙁 , and that was from a 14 year old Scottish guy who though t it was hilarious that his surname was Roche too).