I posted that old photo Tom Hay sent me and I saw this "When Mark Zuckerberg called for a "Space Hackathon" to decorate Facebook's massive new headquarters at 1 Hacker Way, he probably didn't expect employees to take him so literally. A few scurried up to the roof with some tar paint, and now there's a 42-foot wide QR code on the roof that's visible from space".
How many of you have created advertising on a roof?