Michael Fassbender turns 37 today, and the fassinating actor is one to watch. We first set our sights on the sexy Irishman when he bared it all as a sex addict in Shame. Then he spanked Keira Knightley as psychiatrist Carl Jung in A Dangerous Method, and he's done more than one striptease in magazine photo shoots over the last few years. Did we mention he speaks fluent German and is set to star alongside Ryan Gosling in an unnamed Terrence Malick project? Besides his devilish grin and proclivity toward playing naughty bad boys, here are a few of the many reasons Michael Fassbender is on our sexy radar.