Sleeper is an ambiguous term. I'm defining anyone on less than half of Yahoo! rosters as a sleeper in the interest of providing clarity. Typically, I'll aim to feature players on fewer than 40 percent of rosters. However, this provides me some wiggle room.
Don't worry, deep-league gamers, this piece is intended to help folks in leagues of all sizes. With that in mind, I'm following my predecessor's lead, including honorable mentions. If the featured players are already rostered in your league, the honorable mentions should provide you with players to consider filling in for an injured starter or player on bye on your roster -- or for whatever other reason you're diving into the free-agent pool for a sleeper.