We’re sure you know that Justin Bieber has got naked a lot, over the last few years – so we thought we’d do a nice little round-up… you know, in case you’d lost track. Justin celebrates his 23rd birthday today (March 1st), but the best thing about Bieber is that if don’t even gotta be his burtday, for him to wear his birthday suit – or even for there to be a little cake…