This made the Beowulf list yesterday, and below is what I wrote in response: "Seagate ST31500341AS 1.5TB Barracuda 7200.11 SATA 3Gb/s 3.5″

This made the Beowulf list yesterday, and below is what I wrote in response: "Seagate ST31500341AS 1.5TB Barracuda 7200.11 SATA 3Gb/s 3.5″ Aargh! Should be definitely substituted by 2 TByte WD RE4 drive. Today I've built a 32 TByte raw storage Supermicro box with X8DDAi (dual-socket Nehalem, 24 GByte RAM, IPMI), two LSI SAS3081E-R and OpenSolaris sees all (WD2002FYPS) drives so far (the board refuses to boot from DVD when more than 12 drives are in though probably to some BIOS brain damage, so you have to manually build a raidz-2 with all 16 drives in it once Solaris has booted up). The drives are about 3170 EUR sans VAT total for all 16, the box itself around 3000 EUR sans VAT. I presume Linux with RAID 6 would work (haven't checked yet), too, and if you need more you can use a cluster FS. Maybe not as cheap as a Backblaze, but off-shelf (BTO) and you get what you pay for.