So I found this web site for Calling America that lets you make free phone calls to the United States. It seems to be fully supported by advertisements on the screen. You just type in the number and then you get a pop-up asking if it can use your microphone. You also have to wait 10-seconds before it dials (time to read the ads).
Not the best quality, but if you’re over your minutes it’ll work. My most likely use is when I’ve misplaced my cell phone, since it’s my only phone I don’t have a way to call it and have it ring…
I’ve tried a few calls on it so go check it out. You’re limited if you don’t sign up for their free service (numbers of calls and time length).