Next: Posts that spray a logo on the clothes of passerbys.
The ink is washable, but part of the campaign also deals with popularizing the idea that wearing clothes with spray-on logos gives you street cred as a cool dude who is on the move.
Follow Up: Advertising operatives come to your house while you sleep and tattoo the logo backwards onto your forehead. When you wake up and go to the bathroom you see it in the mirror.
Also considering the flash is bright enough to cause a long enough afterimage, it could be bright enough to cause retinal damage in some people, meaning they'd be seeing the BMW logo PERMANENTLY.