How Do I Watch Prison Break Online For Free?

 I watch prison break at www.fox.com/prisonbreak but they only play the current season. You can watch most of season three there but for the other two you might want to try youtube.com. I don't know how much of each one they'll have but they do have long clips of some. When I started getting into the show that's were I watched it at. Also there's gong to be a season four (YAY) if you didn't know.