Streep for sure, Morgan Freeman, Helen Mirren, Julia Roberts (although I think she is somewhat overrated), Cate Blanchett, Rachel McAdams, Johny Depp and also I'd like to mention the late River Phoenix... he had it!
oh I love Alan Rickman in Harry Potter..........that is by far my fave of his acting career!
But I have to say my all time fave is Anthony Hopkins. I met him before, actually I used to see him every weekend at this restaurant I was a manager at. He is so awesome! Very humble about himself and his career and hysterically funny!! He introduced himself to me as Tony. What a crack up!! And he used to walk around the restaurant making this crazy slurping noise saying "Clarisse" to his regular waitress Shannon. It was the funniest thing ever, it used to freak her out!!