I use gizmo. Using my computer on AC, I think it's .22/minute to call a Belize number, ~.1/minute to call any number in the US, and free to talk to someone else on the software. It's a flat $5/month fee to have a VOIP number, and if my Mom calls me on that number, the call is free for me. She's in the same area code, so she doesn't pay either. The only problem is that I can't call Belize mobile phones (that may be fixed, haven't tried in awhile).