You could probably get that much power in a Mac Book, Mac Mini, or an IMac. If you already have a monitor, keyboard and mouse, the Mini can get data to an external firewire drive at a good speed. The difference in the two models is really the burner, the higher priced one can burn DVDs. I've lived through all their architecture changes, and my small tip would be to go with an Intel Mac.
I'd second that.
Actually, I bought a MacBook Pro tonight. Don't need it, though.
Went to Best Buy and found one (open box) for $999.99. I assume it was mis-priced somehow, or something. I immediately put it up on Craigslist. Already sale pending.
Now, I'm trying to decide if I want to use the cash to buy either an LCD TV (I was actually at Best Buy shopping for an LCD TV in the first place), an X-Box 360, or a MacBook (I already have a desktop replacement class PC, but I'm looking for a new portable to replace my aging G3 iBook and - yes, Powerbook 1400).