http://mediasonicinc.com/store/product_i..._id=150%20
This is a Great Box!
4 bay enclousre, auto power on/off with htpc connected either usb2.0 or esata. (Esata needs an htpc with Port Multiplier support. Rosewill has a two port esata with Port Multiplier support PCIE-1X for around $24 newegg)
(Think WOL from either a smart remote like andorid or iphone or from another xbmc box, main systems powers up with HD's, saves $$ on energy costs and proloings life of HD's, use 5400 green drives)
Support all 3.5" SATA I / II / III hard disk drive up to 3TB
Transfer rate up to 480Mbps via USB 2.0
Transfer rate up to 3.0Gbps via eSATA
Power Sync: Power off in synchronization with PC
Forced Convection Process
Smart Fan function
Thermal-Sensor built-in
Auto & Manual mode
3 level of speed
One button interface selection: Switch USB 2.0 or eSATA interface by pressing one button
Install mdadm and lvm2 and run raid5 or 6 attached to your xbmc box, no need for costly SW or sperate server builds. Mdadm and lvm2 use very very little of your processor. like around 1-3% if not re-syncing and during a re-sync I have no issues with watching movies or using the HD's in network (I can watch a BD movie on my main xbmc/video server and have 3 external xbmc boxes running at the same time with NO problems). A great ROI for $$$ spent with about 90-110MB throughput. A 4TB system would be around $300 if you buy drives on sale or 2 TB drives in raid1 config with room to grow.
Or they have another one that has the raid5 built into the HW for about 20-30 dollars more and no SW on your xbmc htpc. You would still need the port multiplier card unless you use the usb2.0 port.
Or go buy/build a seperate server, battery backup, buy some SW and leave it on 24/7 and waste energy.
Bleeding edge stuff.