Does anybody have any recommendations for which VIOP SIP service whould be the best in the UK. I'm using an N800 with 2008 and the latest updates. I'd like a provider which would work with the intergrated tools within the OS rather than installing more apps such as skype or gizmo.

I'd like a free/cheap incoming number if possible. I've had a look about, and there are quite a few out there, but I'm not sure which one would be the best

Regards
Gaz