It appears that you either need to go to said computer and log out, or may need a temporary ban.
I believe you can change your email in your user profile. I also believe it needs to be an ISP type email (@cox or the like), or something like a work email.
I thought about the changing the password, but I was unsure if it would log the other comp out.
This post was edited on 1/23 at 11:19 am