![Lufthansa Boeing 747-400 (D-ABTD "Hamburg... Lufthansa Boeing 747-400 (D-ABTD "Hamburg...](http://upload.wikimedia.org/wikipedia/commons/thumb/6/62/Lufthansa_B747-400_D-ABTD_FRA.jpg/300px-Lufthansa_B747-400_D-ABTD_FRA.jpg)
Lufthansa is running a competition for up to 1 million airmiles for their Miles & More frequent flyer program.
The promotion is tightly integrated into Facebook and encourages you to share the promotion with your friends – though at least they give you a reasonable incentive!
More info here