> Generally, a HDD sitting there spinning away is not what kill them off,
however turning them on-off-on-off a lot is the most abusive thing that you can do.
--And this is EXACTLY what they should be building/testing consumer-level hard drives to do! I make it a point to buy WD drives anymore, and they mostly last at least 5 years if not more. I R/W scan every sector before putting the drive in use, and spin them down (usually within an hour of idling, but sometimes in half an hour) to save money on my electric bill. And I turn all my PCs and laptops OFF when they're not being used.
--The drives aren't apparently any worse the wear for it; I don't even put fans on the SATAs like I used to do with IDE drives. And my electric bill is usually less than $65/month. With the savings I get there, buying a replacement drive if one starts failing is actually cheaper in the long run