Avencast: Rise of the Mage

I usually hide them in WL and group GA descriptions. Tend to not have many ninjas that don't say thank you.

Maybe a person can write you a message why he wants that game and you will give it away amongst some participants using random numbers.

Do a thread where you ask if there's anyone who has it on their wishlist, and they've had it there for at least a couple of days. Randomize the winner with a die or random.org or something like that.

you can spot an active user (some one that you see often, someone with a factory next to them ... ) and look their game library and if they don't have it, you can give them directly (adding them to steam )

http://www.keygiveaway.com/ if your just worried about bots as for ninjas no idea though

I've seen some people just ask for people to post in a thread they make up that are interested in the game (could still have restrictions on who is eligible, I guess) and then they go by the post numbers and "roll the dice" that way. Then they just add the person on Steam and give them the key that way.