Arduino Mega2560 as ISP to program another Arduino Mega2560

Other Hardware 3rd Party Boards
17

It would be nice of some can figure it out how this works. The you could program any Arduino with the 16u2.

See this and this:
https://groups.google.com/a/arduino.cc/forum/#!msg/developers/V_T-Uvj8hSs/h9xlGyM9cJoJ