I have some great news. The OSX SAT SATA driver adds support for some external drives, connecting over Firewire, USB, or eSATA. I have tested it on a drive I owned, and it worked just like an internal drive
Supported external drives have been the number 1 feature request since SMART Utility’s release 6 years ago. I’m estatic that I can say its (mostly) supported. Not all drives will work, but the best way to know is to try. Just download the zip from that link, open up the .dmg, and install the .pkg. Many thank yous go out to kasbert who wrote the code.
Because its based on Apple’s code, it uses Apple’s public license. This means that in the next version of SMART Utility, I will include a way to install the driver. That will help so many people.
Look for that new version soon!