I've been looking for a very simple enclosure with 4-5 HDD bays with unRAID builtin to the port replicators; providing one large logical drive.  There is a Drobo-s product that hardware-wise is perfect; except it's been reported to be somewhat unreliable and it's definitely way too over-priced.  Is there such a thing?  I definitely don't want to dedicate an entire PC to do this.  Thanks in advance.

Contact lime-technology directly.

There was mention of some new servers coming out in the future which may suit your needs perfectly.

I can build you a box with six bays and e-SATA based on an HP MicroServer. PM me if interested.

there are many ways to do this with an itx board and processor for cheap (basically what a drobo box or other similar "NAS" hardware is inside).  you can get them running using less than 30W when Idle (heck, my i3 rig with 10 drives, switch, and second Atom server plugged into the UPS RUNs - all drives spun up, normal load - at 120W right now, and if I remember correctly it idles down around 40 or 50W - 2 "servers" and the network switch, so very reasonable).