En Vogue says, "free your mind, and the rest will follow." Funkadelic says, "free your mind, and your ass will follow." Metolius says, "free your nut, and you won't have to buy a replacement."
The Metolius Freenut is a "nut tool," which is at least twice redundant in my admittedly limited and gutter-friendly lexicon. Crotch jokes aside, it's something every climber should have on their rack unless they like leaving behind $70 cams for the next guy to extract.
The Freenut has a mushroomed end to smash in frustration without bloodying your palm, and a built in clip to save a 'biner. The curve allows you to more easily get behind a difficult piece, and that's not a crotch joke, I swear. Other than that, not much else to say. It's a simple but useful tool, much like my climbing partner.