Help me build an inexpensive NAS

All,

Since the pre-built NAS systems that are currently out have issues or don't have good reviews I guess the next step is to build my own. I have an old PC that I was thinking of using but it may be too old. Having said that can you build a NAS excluding HDD for around 400-500 ? and what components should I get/need.

Thaniks

How-to: Mini DIY Project: 2TB NAS Box for $360

http://boredsysadm.blogspot.com/20 [...] x-for.html

Product Description Unit Price Total Price
1 Rosewill R223-P-BK 120mm Fan ATX Mid Tower Computer Case - Retail
$19.99 $19.99
1 Foxconn G9657MA-8EKRS2H LGA 775 Intel G965 Express Micro ATX Intel Motherboard - Retail
$49.99 $49.99
1 Antec Basiq BP-350B 350W ATX12V Version 2.01 Power Supply - OEM
$9.99 $9.99
1 Intel Celeron 430 Conroe-L 1.8GHz LGA 775 35W Single-Core Processor Model BX80557430 - Retail
$37.99 $37.99
1 Kingston 1GB 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Desktop Memory Model KVR800D2N6/1G - Retail
$14.99 $14.99
1 OS FreeNAS
$0.0 $0.0
1 OS OpenFiler $0.0 $0.0
3 Western Digital Caviar SE16 WD6400AAKS 640GB 7200 RPM 16MB Cache SATA 3.0Gb/s Hard Drive - OEM
$74.99 $224.97
3 Optional Part: iStarUSA T-5-SA 1x5.25" Bay Trayless Anti-vibration SATA Mobile Rack - Retail $14.99 $44.97
Subtotal: $357.92
Subtotal (with Mobile Racks) 402.89