This is really one of the coolest things I've seen in a while.

As part of its Kids in Sports issue, ESPN The Magazine asked 12 stars to write letters of advice to themselves as younger athletes. Some of them submitted handwritten notes, including Green Bay Packers quarterback Aaron Rodgers, and his is revealing on so many levels.

Rodgers focused on a relatively unaddressed junction of his athletic career: The impact of a serious knee injury while playing pickup basketball in high school. He writes: "Thanks to that injury, achieving your dreams will be that much more difficult."

Encouraging his younger self to fight against the urge to quit football, Rodgers added: "The journey is sweet. So try to enjoy it as much as you can."

I don't know. There is a certain authenticity in a handwritten note. Style, pace and (yes) penmanship all reveal unique layers of Rodgers' personality. Even the first sentence -- "Just let the ball go out of bounds." -- is a relatively sophisticated device in delving into the topic.

You can read all 12 letters if you want, or click on the image in this post to view a larger version of Rodgers' tome. It's worth your time.