Channel 9's own Dan Fernandez has come up with one of the coolest hacks I've seen recently. TweetCraft is a Twitter client that runs within World of Warcraft. It allows you to tweet, read tweets, automatically tweet your acheivements, and even post screenshots through TwitPic. The app can be downloaded by going to http://c9.ms/TweetCraft/. You can also read the FAQ here, the Getting Started Guide, or read how TweetCraft works. Dan even had a video made, which you can watch here (left).