You took the words right out of my mouth there RCFlyer, on the hard drive front at least.
If you're building one yourself (or getting a mate to) make sure you go with SATA (versus EIDE) - it's at least 30% faster but the same price! (At least over here they are
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)
There's no machines you can buy off a shelf that I know of with SATA drives in. Bloomin' shame really, given that your HDD is likely to become a major bottleneck in the system fairly quickly...