I've recently completed a project to compile publicly-available NFL play-by-play data. It took a while, but now it's ready. The resulting database comprises nearly all non-preseason games from the 2002 through [edit: 2012] seasons. I have not performed any analysis on the data, so what you'll get are the only basics--time, down, distance, yard line, play description, and score. It's almost exactly
![Advanced Football Analytics (formerly Advanced NFL Stats): Play-by-Play Data](https://cdn-ak-scissors.b.st-hatena.com/image/square/2bf4047626b386ac5292c3ad6541cf824ebaaa08/height=288;version=1;width=512/http%3A%2F%2F2.bp.blogspot.com%2F_ksxjg7CFQxA%2FS9j4_mWJxTI%2FAAAAAAAAJ2Q%2F0i6udNQ3AQ0%2Fw1200-h630-p-k-no-nu%2Fpic.jpg)