Here's a cool new concept. Grafedia is effectively an online repository of image and audio files uploaded by ordinary folks to their server. But what makes it unique is that the only way to retrieve the files is by seeing handwritten graffiti on walls, trains, benches, or any object, and then sending an e-mail.

The rule is to write the grafitti in blue, with an underline, just like standard hyperlinked text.

For example, you could write "Hillary Clinton for President" on a wall somewhere.

Go ahead, click the hyperlink. It will open up an e-mail window. Just send the e-mail, WITH NO SUBJECT LINE, no message, nothing else. In a few moments, you'll get an image back in return.

See how powerful it is?