I sure have luck with roommates.
So after OR (as I once called him) came back from Las Vegas, I spoke with him about changing the amount of rent we each paid to be more fair. He agreed. Then, he changed his mind. And forgetting that I am on the lease same as him and should have some say in the matter - and that we had reached an agreement - he proceeded to give me several figures (six in total) of the "new" amount I should pay. I decided this was absurd and found a new place. He told me to go ahead and pay half rent, so I did. Then he decided this was insufficient and refused to sign the paper to take me off the lease, because he misunderstood how long I was going to stay in the apartment this month. So the paper is sitting there and I will have to try and convince the apartment manager to take me off without his signature. Meanwhile I suspect I will have to pay him more to get him to forward my mail to my new place. The funny thing being that this would make the second time that I had a roommate retroactively raise the rent after I was on my way out, and just like last time, I am probably going to have to pay because I won't be able to give everyone my new address in time.
(And of course all my friends are quick to suggest that I find a more . . . permanent roommate.)