USA, Canada / Most economical way to call Poland from US [6]

Skype probably doesn't use as much as you think, especially if you turn off the video.

Per the thread below, your 5GB is good for 160 HOURS of Skype.

forum.skype.com/index.php?showtopic=62535

Or to put it another way, it may be cheaper to up your internet plan than to pay for a call. :)