If your budget allows it, you could pick up one of these
I've got one of those drivebays built into my case [a Thermaltake BTW] and it's hooked up to a SATA3 port, so is pretty quick when using SATA3 drives. It was a damned good investment, this case, as I have several drives that no longer need external caddies to access their contents.
However, I have been considering something along the lines of this 5 drive SATA caddy...


As you can see, it has 5 individual SATA ports to access all drives simultaneously, but it only requires 2 power connections to fire them up. Being that I have a PC upstair and downstairs, plus Shaunna's and a guest machine, I figured such a caddy could be the way to move them between PC's as a whole rather than being carried around loose... I think they'd be easier to drop that way. I'm looking at around $180 - $190 AUD from the company whose banner is across the pics. However, that is quite reasonable, I think, given it's free shipping from Hong Kong and the same or similar product would likely cost me twice that in Australia... PLUS shipping.