free calls to any number USA unlimited

this is a roundup of services that will give free calls to the US on a completely unlimited basis without any payment:

earthcaller - very easy to use, consumer oriented

icall - you must download the client adn register, incoming calls also possible

grandcentral - callback must have US phone number.

switchvox - also free calls to many other countries. avialable to users that signup for a free trial of the switchvox PBX. you share an account with all other free trial users. can register your SIP device. you can learn a bit along the way with this.

voxeo - you get a free bussinessvoip account when you sign up for the evolution developer platform. this is a sophisticated platform that allow the creation IVRs and other voice and call enabled services. there are no preset limits on use for 'testing purposes' you will be politely asked not to make calls for bussiness or personal use. this option is a bit complex and requires a powerfull PC to download and run the non-hosted end of the service. i would not recommend it if your goal is simply free calls; there are other much easier options.

there are many other options that give you 10 min. calls or a certain amount of credit, etc. but why use them when you can use these unlimited?