Dota 2 Giveaway Ideas

I was just given 5 copies of Dota 2 on Steam that I don't know what to do with. Pretty much all of my friends that are interested in the game already have it, so I was thinking of doing a giveaway to hand them out to people. I'd also like to be able to use this giveaway to increase the visibility of my blog if at all possible, so if you have any ideas how I should do this giveaway, feel free to leave a comment here or send me a twitter message (my twitter link is in the left column at the top).