About 6 months ago, I visited Bluefruit Software. To help them accelerate the learning for team leads, I introduced two teams to Mob Programming. (See www.mobprogramming.com) A few weeks later, they blogged about it here http://www.bluefruit.co.uk/training/mob-programming-nancy-van-schooenderwoert/
There are a lot of remarkable things about Mob Programming, and sheer contagion is top of the list for me! With no prodding from me, they immediately started to use it for some aspects of their work. No one pressured them to use it - not me, not their mangers. I suspect that is part of the reason it got adopted there; they could own it.
In eXtreme Programming there's a saying "The simplest thing that could possibly work". I think of Mob Programming as the craziest thing that could possibly work:-) A whole team at one computer; everyone thinking and conversing about the work at hand while one does the keyboarding. To see what this looks like, check out the 3-minute video at https://www.youtube.com/watch?v=p_pvslS4gEI