I recently saw a TV add for phone service using what looks like a bluetooth key plugged into any computer to get free local and domestic long distance for about $40 the first year and then $20 each year thereafter. Since my IMAC already has bluetooth I was wondering if there was some way I can plug a phone into my computer to make free calls? If you are doing this, can you explain how you are doing it? Does it work with cell phones or do you need a phone with a regular phone jack? Do you need to register your phone number somewhere to keep your existing phone number? I've heard of people using a computer to make phone calls for years but never understood how they are doing it. Thanks for the help!