This is the new acropolis museum, designed by architect Bernard Tschumi.
I don't like the pillars that seem to be painted on the side--but I'm no fan of pillars on anything new.
That said, I think the top of the building, situated parallel to the acropolis, is very nice. And the inside of it, from what I've seen so far, is very nicely laid out.
All in all, it's an interesting building and if I had to rate it on a scale of good to bad, I'd rate it a good one. Click through to the link for some other views. And leave a comment here if you have any thoughts on it.