After some research, I discovered how to legitimately make free calls with Skype.

1) Download skype software for free.

http://www.skype.com/download/skype/windows/

2) To call US & Canada businesses only (not residential), use Google 411. Since Skype allows you to call any 1-800 number for free, then this works!

    Google 411 (1-800-466-4411):
    http://www.google.com/goog411/#utm_campaign=en&utm_source=en-ha-na-us-bk&utm_medium=ha&utm_term=google%20411
   
    How To Use With Skype:
    http://www.youtube.com/watch?v=kqDsl7CnCWg

3) Free 5-minute phone calls to mostly anywhere in world. There's an add you're forced to listen to.
   
    How To (1-800-373-3411):
    http://www.youtube.com/watch?v=fymSI6chwuc

I imagine this approach can be used with other services such as Yahoo Phone Out.