A slight necro - but looking on Scan today (as you do...) I noticed the legendary Samsung HD103SJ down to £90.12! Seems like they are coming down! I just hope they get below £50 before April - the need for a decent file server is growing.
I've seen an external 2TB drive at around £71.99 at scan on 30th Dec. This seems to be the best way of getting the high capacity drives, by buying them as external drives.
I was in the Scan shop last week and saw a 2TB external HDD for little over £100, maybe you could go down that route and rip it open?