Artist Michele Banks uses watercolor to depict natural, scientific, and medical phenomena. This one above shows cell divisions (note that it's not meant to be completely accurate); another one I like is a bright blue canvas with a single line showing someone's heart rate. Her work is available for sale in the Makers Market/Boing Boing Bazaar!
I'm a contributing editor here at Boing Boing. I also have a blog (TokyoMango), a book (Urawaza), and I freelance for Wired, Make, the NY Times Magazine, PRI's Studio360, etc. I'm @tokyomango on Twitter.