Citizen Engineer is an online video series about open source hardware, electronics, art and hacking by Limor (`Ladyada') Fried of Adafruit Industries & Phillip (`pt') Torrone of MAKE magazine.
In part one of this episode dedicated to phone hacks, you'll learn how a how to build your own SIM, or Subscriber Identification Module, card reader and receive tips on viewing deleted contacts and text messages.
In part two, you'll learn how to modify a "retired" payphone so it can be used as a home phone and/or for VoIP (Skype). You'll then learn how to modify the hacked payphone so it accepts quarters. And, lastly, you'll see how to use a Redbox to make "free phone" calls from the modified coin-accepting payphone.
For more information on any or all of the above hints and hacks, take a look!