In theory you just need an interposer to use SATA drives in a SAS enclosure: http://www.dataonstorage.com/dataon-products/6g-sas-to-sata-... But that still doesn't solve the problem of the JBOD itself costing more than the disks (less so with SSD) or ZFS costing more than hardware RAID, etc.
I'll start with what I know firsthand: those interposers are not supported for many technologies, including Windows Server Clustered Storage Spaces. This is straight from DataOn storage reps.
And what I know second-hand: many SATA SSDs have terrible failure modes in the form of RESET storms when behind an interposer. That is, you can end up in a situation where you have to shut down all hosts attached to the SSDs and power them off before they return to life. Not a good situation. The interposers apparently greatly exacerbate this problem.
I will check out your link on networking, thank you :)
For (relatively) cheap networking check out http://www.colfaxdirect.com/store/pc/home.asp