Chow Yun-fat. I know he's revered as a god in some parts, and I risk being flayed alive for saying it, but I just don't get what all the fuss is about!! Back in the 80's and early 90's, he was lauded for being 'super-cool' in a string of hugely influential movies, but I couldn't understand what made him stand out from the crowd. Is it simply charisma? Perhaps. But there were plenty of other actors working in HK cinema at the time with just as much screen savvy - I agree with earlier comments that Andy Lau (for example) is generally underrated as an actor, and is no less charismatic.
At the risk of sounding ungracious, I don't think Chow is particularly attractive (not ugly, you understand - just not conventionally 'handsome'), and while that may strike some as a superficial response - what can I say? I'm a sucker for a pretty face!!

And as for being 'cool', I always thought Chow was completely 'out-cooled' by Tony Leung Chiu-wai in HARD-BOILED (check out the library sequence, early in the film, for a perfect illustration). In fact, the reason I never really thought much of Woo's THE KILLER (beyond it's remarkable technical achievements) is because I'm not a fan of either Chow or Danny Lee, which meant I was unable to engage with the characters in a meaningful way.
However, no one should mistake my aversion to Chow as an attack on his acting abilities. He didn't reach the top of the HK movie tree by being a hack in the thesp department! No, his acting is just fine - I'm just deeply confused by the god-like status he enjoys among Asian-movie fans.