So build my own NAS box was the mantra. What I needed:
1. Cheap processor with low power consumption
I already had a dual core 330 Atom board at home, just had not found a use for it. This CPU would be perfect for the NAS.
http://www.newegg.com/Product/Product.aspx?Item=N82E16813121359
Cost Rs 3500.
2. Small cabinet that does not take up space or power and makes no noise.
This was the tough one, especially in India. After a lot of research, I zeroed in on the Panache T3300 as the cabinet. It is small, in fact really compact and runs off a DC power board. This means that there is no PSU in the case (hence no fan/noise) and it runs off a DC adapter like a laptop. Disadvantage is the lack of a DVD drive.
Note the Panache box kept next to a WD external hard disk and a encyclopedia to get a idea of its size ! :bleh:
http://panache.co.in/store/product_info.php?products_id=111
Cost Rs 3200.
3. Operating system for the NAS box
Lot of options here. Windows embedded, standard linux distros and more. But what caught my eye is the FreeNAS distribution. It is a embedded OS that runs off a 200mb image, configured completely from the web and works like a charm on the Atom. More importantly, very configurable and very expandable. Just perfect for my needs ! :hap2:
http://www.freenas.org/
Cost Rs 0 !
4. Install disk for the OS on the NAS box
An 3.5" disk is out of question on the small panache box. A 2.5" disk is acceptable, but still draws 4-8 watts of power for no reason. And the minimum size is 40gb when I just need one GB of space.
A little more research got me onto a fantastic solution. I found out that there are IDE adaptors for compact flash cards for about Rs 100. The bad news is that a compact flash card is expensive. But here also, I stumbled across a great solution. A CF adaptor that used cheap SD cards internally !!!

A 2GB disk for a grand total of Rs 1000 and uses 0.2 watts of power!!!
http://dealextreme.com/details.dx/sku.711
Cost Rs 100
http://dealextreme.com/details.dx/sku.22338
Cost Rs 700 + Rs 200 for a SD card (Be a little carefull when you buy a SD card. It has to support DMA access, otherwise the OS will not install on the disk)
5. Memory. Less is more in this case !!!
A 512 DDR2 stick would have been plenty, but I had a spare 1GB stick with me and used it. Can hardly see any difference in performance between this and a 2gb stick.
All set, I assembled the Atom box and made sure everything is working.

Now is the time to download the FreeNAS OS and boot off the OS with a external DVD drive. There is a nice option to install the embedded system to the disk. Choose this and install the embedded FreeNAS OS to the attached compact flash drive.
Attach the external USB drives that you want to share, assign a IP address and reboot the machine. When the machine is up, you can connect to the headless machine from a browser at http://myfreeNASipAddress and configure the machine, the attached drives, the network shares, the services and everything else from the web !!!
You are all set. The network access is extremely fast and you can add as many USB drives as you want and share them on the network either cvia NFS or Samba. You can even setup software raid for the drives that need protection.

The NAS box up and running, attached to a monitor. See the power being drawn on the side. Just 0.11 Amps, which translates to a grand total of 25watts for a fully running NAS box. :hap2:
Total cost of the setup was Rs 9k without the external hard disks. For a NAS server that is expandable to as many USB disks as you want with RAID and multiple share options, this is worth it !