I am a big fan of sunglasses. Can't have too many in your wardrobe. Not kidding about this, at any one time I have at least five different styles in my car, ranging from dark dark to clear, jeans wear to suit and tie. Be prepared.
Clear ones are really handy. Not only do they look cool, but they're great for keeping stuff out of your contact lenses when you're driving around with the windows down at dusk, or later. Check out clear Ray Bans. Very cool, appropriate for business, club wear, and lots of points in between.
I'm a big fan of Ray Bans. I own many pairs. Only caution: don't buy the ones that have thin wire side pieces (the part that goes from the lens to your ear), or they'll get bent in a short while, and you'll be mad that you spent so much money on such flimsy shades.
A great tip: the $10 sunglasses rack at Nordstrom. Their mirrored aviators are great. I get lots of compliments when I wear them. Sturdy, a great design. And yes, they were only $10. Can't beat it.