I'm not sure how much you're willing to spend or how large of an NAS you want to go with, but I have had good experiences using the WD MyBook line of NAS as well as Buffalo NAS drives. Both are a little bit larger to accommodate multiple drives, but get much better airflow and cooling because of it.
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Intel Pent D 820 Smithfield - Intel D945PSN
eVGA 7800GT OC - 2GB OCZ Gold Series DDR2
Logitech Z-5500 *I like to feel my video games*
