Ever wished you could be back at school, but without the awkward lunch room/locker room/school bus situations? If so, you should check out the Khan Academy. Sal Khan has videos on pretty much everything (although lacking in the area of history a bit).
I found this one on communism. If you’ve never read Marx’s Communist Manifesto, this is a nice little crash course. Khan’s political leanings are clear, but he does a great job mapping out different types of government and how communism came about, how it works, and where several modern nations stand today.