Tricycle has a page up called Hacking on Less Wrong which describes how to get your very own copy of Less Wrong running on your computer. (You can then invite all your housemates to register and then go mad with power when you realize you can ban/edit any of their comments/posts. Hypothetically, I mean. Ahem.)

I've updated it a bit based on my experience getting it to run on my machine. If I've written anything terribly wrong, someone let me know =)