I've seen multiple. The one I like is 'pinks and blues' where you're given two of each - a pink and a blue - and you write out why you think two dudes should get a blue (good) and a bad (pink). If you start accruing a bunch of pinks, there's a problem.
It's very simple and probably wouldn't pass muster with an HR department, but it was effective at getting rid of turds.