When a user is suspended, their account is reduced to 1 rep and all of his privileges are stripped. However, they can still join chat rooms.
This leads to various forms of possible abuse (all of which I've seen by suspended users):
Suspended users cannot be kicked, and even moderators can do very little (aside from completely removing the account, which is often overkill).
My proposal is to extend profile hiding for suspended users to one of two levels: