Another SIP-based service has started up: Free IP Call. They are in Europe (it appears) but anyone can sign up for a free account. They support SIP and as such, users receive a global SIP address of the form firstname.lastname@example.org and Free IP Call users can place calls to any SIP address on the Internet (such as FWD, IPTEL, or Sipphone) but of course NOT to proprietary non-SIP-standard services like Skype. They do not (yet) support ENUM, but plan to next year.
give me a account