3x120 on top was already discussed, possible, takes 1 cd drive, which is fine, you can put there fan control panel, or even aquaero. I wouldn't consider hdd space at all, since these days everyone should use SSD which are tiny and can be fit almost everywhere. In my rig, if i ever plan regular hard drive, it would be data storage 2TB 3,5'' one in scythe quit drive, laying on bottom of the case.
As for psu mount, there is very nice trick for this case, eats up 3,5'' bay and requires little cut:



It isn't my picture, belongs to user MS1000 from pclab forums, I belive mounting psu like this was his idea as well.
This case is really interesting, you can put full atx sli rig with enough rads, despite fact case is so small.