During the writer's strike Joss created an online project. The premises is is an evil genius blogging about how he is going to take over the world with musical interludes. There are three episodes up at www.drhorrible.com
The episodes are free until the 20th and then they go up on the Itunes store. So hop on it!
I just finished the first one and it is hilarious. The third one comes out on the 19th