Whistle Phone is a free app that let's you make free calls anywhere in the us! You even get your own number. This is one of my favorite apps. The one problem I have is that there is no push so you need the app open to receive calls, but, when IOS4 is released in November, we can you multitask so it can be open while in other apps.
awesome, Im a lil late tho, I just paid 10 bucks for Skype credit, but I will check this out seems too good to be true!
I think Skype charge 60 dollars for 3 months to have your own phone #.
I use Whistle and people tell me that it sounds great. The two things to know about Whistle is that it assigns you a phone number. You don't get a choice. I live in Missouri but my Whistle number is in West Virginia! The other thing to know is that because it is free, when you dial a number, you have to listen to a short advertisement (20 seconds maybe?) before your call is connected. Of course you are also given the option to place a call to the company who's ad you just listened to!