One of the interesting items on display at last weeks BOSFCPUG + BOSDSLR Mixer was the Sohotank, a drive storage enclosure available in two, four and eight slot configurations. An 8-bay unit was brought along by local reseller, Stuart Cummings of Watermark Productions.
The four and eight-bay Sohotank units are available in models that support eSATA or mini-SAS. In addition to the Sohotank models, there are also Sohoraid models. The
4-bay Sohotank ST5610 and the Sohoraid SR4 seem very similar; I'm not
sure of the exact differences!
I'd not heard of these before, and they seem to be difficult to find online; it's not even obvious if you can order them on the manufacturer's website!
At around $600 for the eight-bay unit (I can find no pricing for the four bay Sohotank!) these might be an alternative to the Drobo unit.
Raidon: Sohotank (manufacturer; link to 4 enclosure unit)
Other World Computing: Sohotank (online sales, 8-bay Sohotank unit. Sohoraid also available)
Watermark Productions (Boston distributor)
Amazon: Data Robotics Drobo 4-Bay USB 2.0/FireWire 800 SATA Storage Array DR04DD10
Amazon: Drobo S 5-Bay USB 2.0/FireWire 800/eSATA Storage Array DRDR3A21 [$689/00]