While Skype and other free VOIP services are getting some deserved attention, these services still have enough limits and drawbacks to prevent them from being effectively used as a primary phone. For example, Skype offers no 911 service. And you can't port your current phone number over to Skype. And Skype only works as a free service to other Skype users. Vonage or other major commercial services are much more comparable to standard commercial phone service and can be used as primary phones.