They don't do it anymore as far as I know, but back in the day, they released lots of weather baloons. If you found one, you got $25. I found one on my uncles lease land. It had been there for awhile, but they still gave me the money. I was also quail hunting on Kaw Lake WMA and found a baloon with a card on it with a day care in Witchita Ks, hanging on a willow branch. It had a return address, so I sent it back and got a card from some kids in the day care that wanted to know how far it went. Pretty cool I thought. ;D