Corey, I'm not sure what MMOs are out there that would offer 'free' servers. Perhps if you put up a list of the ones that you might have access to, the question might be clearer for everyone else.
Myself, I'd be up for just about anything... provided my wimpy laptop could handle it until I got a decent desktop. Or even a MU* server of some sort would be nice. Then again, I
am old school.