You should be active in the community and post in the forums.
In the past 3 months I was gifted or won in contests 6 games, not counting the Broken Sword and Empire Earth giveaways or the other free games. As well as a BoD7/CStW steam key.
The community is pretty generous, so if you post in the gifting thread you stand a good chance of getting something from someone who likes that game and wants other people to play it, especially while there's a sale going on.
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The only certain death in the universe is Mother Hitton's Littul Kittons.
Not changing this line until I beat Seven Heroes (2/24/07)