At one point, people expected 'native' Firewire drives to appear.
That didn't really happen. (I've heard talk that some Apple laptops might use Firewire optical drives, but I bet those people were simply confused.)
However, the manufacturers keep bothering with them because it makes it nice and clean to route a cable to a frontplate, like one of these things:
first useful hit on Google.Unless you're out of IDE positions and PCI slots, or have an actual reason to have Firewire hardware around (in which case it'd make more sense to keep it external, anyway, and Firewire cases with the appropriate adapters are probably as cheap as the adapters sold alone), you're best off sticking with IDE, SATA or SCSI... or waiting for SAS, if you're me.
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Yesterday I saw a external Lacie HD in a friend's house. It was connected via firewire 400 but it supports 800Mbps.
Of course, but U320 SCSI will get you 2560Mbps, and SATA will reserve you 1200Mbps per-device (given point-to-point... or do they still play master/slave games there?). Firewire ain't bad for the number of pins used, but there's a reason Apple's RAIDs are FC.
