One of the best turn-based-strategy games ever made is Worms. In case you've never had the pleasure of playing one of the 23 iterations of the franchise, you take command of five or six small animated worms and try to blow the hell out of the opposing team with a ton of different weapons such as airstrikes, bazookas, or even a dragon punch. Hedgewars is free open-source software, released under GPL-v2 license that replaces the lovable nightcrawlers with hedgehogs — and it works beautifully.
[video: http://www.youtube.com/watch?v=u1Y_Pw_TtFo 607×365]
Check out the official site to vote on the next set of voicepacks to be released. You can even submit a request (and send a small donation) for the development team to create a specific costume for your hedgehog. I'm still waiting for my furry little Justin Bieber-hog to be born.