The drives that will run on Firewire bus-power (no other connector needed) are "laptop" size drives (2.5 inch size). The larger 3.5 inch drives need more power than is available on the Firewire (or USB) bus.

The largest "normal" 2.5 inch drive available as of now is Western Digital's 640-gig model. I have that drive in both my main and backup computers, as well as a couple in external cases. So far, they've been fine.

I say "normal" meaning the typical 9mm height for a 2.5 inch drive. For about twice the price, there's the 12.5mm 1TB drive (also Western Digital). It would need an external case capable of fitting that size drive (most of them won't). Here is an example of that drive in "external" configuration: eshop.macsales.com

Hey Bookz,

I got the same drive Mark mentioned above (OWC On-The-Go)
I actually have two, one for edits and one for gigs. They work great are easy to swap out drives if you ever need to go bigger and very fast. I spin videos off of mine all day long with no issues.

i recommend an external enclosure with firewire 400/800 (the acomdata joints are nice) and the western digital WD10TPVT (12.5mm 1TB).

Using a 3.5 Seagate 1TB inside of an OWC Mercury Elite Pro. Looking at the bus powered version of one of those things or the bus powered On the Go in the near future.

thanks for the input. so basically i can use any sata hard drive and use it with a firewire 800 enclosure? i think i have a 500 gb 2.5 sata laying around.

^yes, pretty much