I play mostly 12-team or larger roto-leagues, so the sleeper lists I see published here on a regular basis aren't really helpful to me. Chris Davis isn't a sleeper, folks. Everyone in every league I play in pretty much expected that guy to hit 30 HRs and get 100 RBI this season, and they drafted accordingly.
I define a sleeper as someone who achieves unexpected success. In the interests of my fellow fantasy owners, I'd like to present a list of REAL sleepers to help your teams rebound from poor starts to your seasons.