A present for a photographer?

My friend's birthday is coming up and he is a proffessional photographer. I was thinking of a present for him. I already got him a rain cover for his camera (since he shoots a lot outside) but it's only $8, so I should get something in addition up to $100.
Any ideas?

Maybe buy him a portfolio book to display his best work to get future customers. If he is self employed you could make him some business cards either off you're computer or at a store like staples. Also an in home photo printer, replaceable lenses can be found at best buy. Hope this helps you and he enjoys his birthday!

Well if he's a pro he probably has the basics of what he needs and the stuff he wants probably is way more. But remember he's your friend first so why not take him out to lunch or something, or go on a photowalk with him.

Batteries. Or a new lens cleaning kit. It's something he'll get allot of use out of.

Get a gift card at B&H. Http://www.bhphoto.com

If he's a pro, ANYTHING other than exactly what he needs won't get used. You don't know what he already has, either.

Indeed equipment up to $100 is probably not what might be useful. Try the portfolio book.