Recommendation for a USB 3.0 JBOD Enclosure
A drive enclosure for 4 SATA drives, connected to the host via USB 3.0 and presented as JOBDs is a great and inexpensive method of adding a lot of hard drive capacity to your computer, e.g. for backup purposes. The enclosure model I have bought is the Fantec QB-35US3. It is compact, the fan not too loud and vibrations from the four drives are kept amazingly low. It can be connected via USB 3.0 and eSATA, but USB is simpler because eSATA requires a port with a multiplier-capable chipset, which is rare. At a retail price of around € 150 the Fantec is relatively inexpensive.
One thing I did not test specifically is the maximum transfer rate, but it seems to be in the region of 80 MB/s, which is good enough for me.
And yes, this works well with Windows 8 Storage Spaces.