Buy.com has the Cavalry SATA 2-Bay USB 2.0 Dock EN-CAHDD2B-ZB for $43 - $15 rebate [Exp 6/29] = $28 with free shipping. This two-bay, hot-swappable USB 2.0 dock is perfect for lumping together your odd-capacity drives into one Spanning device. Supports JBOD and BIG (Spanning) configurations.
Bought one of these and even though the price is OK, when running with two HD's it gets very hot very quickly!! I recommend getting a single HD unit.
I agree with # 1. When I need to use 2 drives, I direct the airflow from a fan on the drives. They stay cool that way.
sounds like good information. I wish this outputted esata