What's the most interesting promotion of airline tickets you've heard of?

Sometimes people will send cargo by paying for a seat. Airlines would like to see the seat occupied and will offer it cheaply or free. You simply agree not to take any luggage other than your carry-on. This was promoted within old hosteling guides I had in my younger years :o)

It probably still goes on today...

This is not a promotion but rather a trade stunt, in most African countries, the travel agents are supposed to be locals, so what a foreigner would do is open a travel agency and have a partner to be a local who doesnt take part in daily business transactions (only for name sake to get the business run legally) but as a fee for his name in the business, our local guy gets free tickets to anywhere around the world for him and his whole immediete family, way cool eh..~

Spirit airlines. $39 each way.