I got into a fairly involved debate about Brandon League on the Rotojunkie message boards recently, and as a result did some research. I was arguing that his combination of high strikeout rate, low walk rate, and high groundball rate is pretty unusual. The only pitchers I could think of who had that combination were all really good. As part of the discussion, I collected a list of pitchers who threw at least 40 innings, with a K/9 over 7, BB/9 under 3.5, and GB% over 50%. League beats all these threshholds by a wide margin, so some of the other relievers on the list aren't as good as him. The starters are probably better, since it's tougher to have a high strikeout rate when starting. Obviously the relievers with much better peripherals like Rivera and Broxton are also better. Still, it's an interesting list, and may indicate some middle relievers to target in deep leagues (or if they're ever given a chance to close).
This also may give some idea why I'm so high on Brett Anderson. He's one of only four starting pitchers who made the list, and the others are all pretty good.