Dominic Monaghan!
Dominic is best know for his roles in Lord of the Rings (as the hobbit Merry) and as Charlie in Lost and is featured in X-Men Origins: Wolverine as Bolt/Chris Bradley. He's been on my radar for awhile, as he always combs the hair from the back of his head forward, a tell-tale sign that the front is thinning and/or balding.
Reader James W. gives us the perfect headline for this bald outing: "Dominic Monaghan is human too and not afraid to show it!"
Here's a picture of Dominic in February 2008 at the Grammy Salute to Fashion:
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And here's Dominic in April, 2009:
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You can see that the sides have receded a bit more, but Dominic doesn't care - he's an out and proud baldie and we salute him!