Are you only using SSDs for storage?

I'm in the process of building a dual loop PC-P80 system and I have yet to figure out where my hard disks are going! I am currently using two Raptors (3.5" ones from my old build) and then drives for storage....

I was thinking I could hide a velociraptor or two in the raised bit between the top fan and the external USB connectors, but then with a BD-RE drive I still only have one 5.25" bay free and would need somewhere to put 2-3 2TB drives to equal my current storage capacity....

My only option at present seems to be sat on top of the PSU but that would seem to be without airflow...