A sleeper is defined as something or someone that becomes unexpectedly successful or important after a period of being unnoticed, ignored, or considered unpromising or a failure.
Given the nature of that, I give you two sleepers for 2009, one for each conference:
NFC – this is a easy choice because my sleeper team is the Seattle Seahawks. 2008 was forgettable because of injury concerns to pretty much every single player this season. Their division is as weak as hell and when you have a 9-7 team winning a division like the Cardinals did last year, anything can happen. The O-Line may be an injury risk (Jones and Spencer), but expect Julius Jones and Edge (and Justin Forsett) to run like hell. After all, the Knapp-Mora combination had the Vick thousand-yard season. The improved health of Matt Hasselbeck and the addition of Housh into the WR corps and the development of John Carlson will bring life back into the passing game.
Runner-up: San Francisco
AFC - The AFC looks a little bit sketchy because of the dominance of the Big Time Teams: Patriots, Steelers, Colts and Chargers. However, I think Houston, after numerous close calls, will be the AFC sleeper. Matt Schaub will find a way to be fully healthy (because Rex is his back-up). Steve Slaton is really good and their pass rush is ridiculous. And don't forget, Andre Johnson is a fantasy stud. Kevin Walter is a quiet quality receiver. Owen Daniels is a good TE as well.
Runners-up: Cincinnati, New York Jets,