I think they're wonderful for keeping the sun off of one's face (which is my constant goal in life). They're stylish and useful. But I would never wear one inside.
I've got 2. I bought them when they were in style in London a couple of years back and keep waiting for them to come back into style in the states! I mainly wear mine to the club, but, I enjoy wearing them out and about every so often too They just look so different and classier than a regualr hat IMHO
I don't really like the ones posted at the top (the ones D & G Rockstar posted are a lot more appealing to me) but they can look really cool if they're paired with the right clothes, imo