The Murray Facebook campaign reminded me of this one.
When Porsche hit the 1 million fans mark on their facebook page, it got there faster than any other car company. So to say thank you, they took the names of each of their 1 million fans and made them part of the paintwork a Porsche 911 GT3.
They created a site where each fan can go, type in their name and see where their name is on the car. The car is now on show in the Porsche museum in Germany.