I saw a post on Hacker News about a big tranche of NFL play data being released on the web. Interesting. However in the comments I saw a link to a web app with that shows whether your NFL team should go for it on fourth down, given your yards required for a first down and the yard line you are on.
I would love to make one for the CFL for going on third down. Obviously there's some differences for the CFL. Lining up one yard off the ball for defences means one yard or less attempts are a lot easier in the CFL. Kicking field goals with posts at the front of the end zone rather than the end adjusts the possibility of getting points from field goals. Plus a lot of other factors.
For the Ticats of 2012, with a great offence and a terrible defence, I wonder if the Cats should have went more on third down. They certainly should have thrown the challenge flag more often.