How does one deal with a crazy roommate?

Well you don't...

But it all depends.

If he/she doesn't clean up after themselves, throws parties, makes a mess in the bathroom well you would then have to make some sort of proposal (and no, not the one involving a ring...)

So you could say that you wont pay rent, or you make a trade. Crazy roommate cleans up after his/herself, and then you do something for said person.

But, your crazy roommate may not be messy or whatever. Maybe this person just has a different of looking at life. Doesn't feel emotion because they don't want to get attached. Only thinks logically or rationally, as his/her own way of dealing with the world as we know it.

You haven't given me a lot to work with, with just saying 'crazy' crazy could be anything.... Well it's more than likely that we both have different 'definitions' of the Word crazy...