The folks at Madden NFL 11 put out a list of all plays run by all of its zillion-plus users so far, sorted by average gain. No. 2 is "Cougar Cross", which sounds like Rex Ryan's wife's best-selling video.
In fact, I'm not sure where you find it in the playbook. I've never seen it and I'm away from my console right now. Googling it gets nothing. So it could be that, being average figures, the per-play gain is goosed by a comparatively small sample size. Ian Cummings, the Madden creative director who released these stats over Twitter, didn't say how many times they'd been run. But "Cougar Cross" bagged 11 yards, on average.
The no. 1 gainer may be more useful. FL Drag Under is out of the Shotgun Tight formation, gaining an average of 18.15 yards; one team that has it is the Arizona Cardinals. Of course, you may expect every cheeser from here to Hempstead to start using it this week.
See the full list here (screengrab of an .xls) Cummings also supplied the 50 most frequently called plays on both offence and defense. I'd be curious to know how many of these were served by by GameFlow, the playcalling engine new to this year's Madden.