This video is from the 2010 Oregon vs. Cal game. Throughout the game, Cal linemen were getting up from the previous play, making their way to the line, and then flopping on the ground when the ball was about to be placed.
This has happened many times against Oregon's fast-paced offense this season. But this is the first time I've ever seen a player seemingly taking a "signal" from the sideline to induce the phony injury.
In this case, 3rd string DT Aaron Tipoti comes on for TWO RUNNING PLAYS, and then flops on the ground so Cal can substitute their pass rushers on for 3rd down.