Om points out that Skype is really now going after the same market as Vonage and really all the rest. I don't fully agree, but feel he's looking the right way, just not going as deep as one can.
For 30 euros a year you get a phone number that rings in with SkypeIn. That's roughly 3 bucks a month or half of what the phone company charges for a basic no frill, pay for extra as you go, but unlike the RBOC's and PTTs around the globe, you don't get free voicemail like you do from Skype at that price.
As a matter of fact, all the third part voice mail services cost more per year than just having a SkypeIn number, even if you never had it ring on your computer or PDA.
Buying some SkypeOut credits still for the Pay as You go type or low volume caller is also a Bell disruptor.