any case can be fanless, just remove ther fans that are there The problem you will face is that if you are cooling everything with watercooling you are going to have to find a way to shift a lot of heat out from your radiators, without fans this may be tricky.
I'm getting a Zalman Reserator1 BTW. Instead of getting a P-160 and taking out the fan, was wondering if I could get a case without any fans. Don't mean anything like a heat sink cooled case, just a case thats supposed to have fans but doesn't. Do OEM case's come with fans?