There are stories all over the internet about people wanting artists to produce work "for exposure". If you're thinking about offering this, do us all a favor and don't. A lot of us trained for years to be able to do what we do, and it's how we put food on the table. It's hard enough for a freelancer to get anywhere near fair rates, and chances are your "exposure" won't have as positive an impact as your money would. If you want good art, pay for good art.
Rock on, guys, and never stop drawing.