Full disk encryption does seem to be the obvious solution. I don't bother personally as the risk of monetary loss due to someone nicking one of my hard drives seems low.

iolo System Mechanic:

Employs multi-pass military-grade wiping to ensure complete removal of all deleted data.
Defeats forensics recovery techniques...

Just marketing hype?

In reply to a post by Pipexer:

I am not aware of any data recovery firms who can recover data from a drive that has been zeroed, but willing to be proven wrong.

I'm not sure what you mean by "zeroed". I used to work for a mainframe manufacturer and we sometimes got requests from customers who had corrupted disks and no [recent] backups.

On one occasion, I was sent a disk pack and was asked to check it out. It was mechanically sound but unreadable by the OS. I had access to engineering software that would pull data directly off the read heads. A lot of the data was OK but a good number of blocks had data shifted a few bits by a faulty drive controller. A lot of the corrupted blocks were directory entries which didn't help. I could have recovered 90% of the customer's data but when I quoted them for the work, they soon decided to re-key their data.

So, yes it can be done but customers often decide to take the cheaper route in the end. Sore fingers do not hurt as much as sore wallets.

In reply to a post by 4M2:

iolo System Mechanic:

Employs multi-pass military-grade wiping to ensure complete removal of all deleted data.
Defeats forensics recovery techniques...

Just marketing hype?

I believe so.

In reply to a post by billford:

when we had to dispose of classified HDDs at Aldermaston, they were stripped down and the magnetic coating sandblasted off the platters.

You were more thorough than the good people at Burghfield. They put their disk packs in a machine that looked for all the world like a large cement mixer full of cannon balls. Obviously, they couldn't afford to buy a sand-blaster. Still, it did the same job in the end.

In those days the disk packs themselves looked like free standing washers.

I used to work with one of these. http://www.cucumber.demon.co.uk/geccl/4000series/408...

State of the art - once.

We had an old General Electric machine. The disk drives had hydraulic head actuators (I kid you not.) The engineers hated it when an actuator sprang a leak - there would be hydraulic fluid all over the place and they had to clean it all up. They danced on the rooftops when voice-coil actuators were introduced.

I have no answer to that.

The engineers had a few choice phrases - all of them unprintable.

In reply to a post by Pipexer:

Did they get you to run any sort of basic deletion first?

I doubt it- you know the Civil Service, an HDD was only junked when it stopped working

On paper that process described is adding a great deal of "surface" for the disk or platters to go missing or be stolen.

You can't get data off a platter that has no magnetic material on it... I don't think they cared about the waste grit, on the principle that if someone wanted to extract all the magnetic dust and reconstruct the data (cf your shredder comparison) they were welcome to try

Talking of shredders... shredded classified documents were collected and incinerated on site, again with witnesses signing it off. Ditto for floppies, which were still in use at the time. And you stood more chance of winning the lottery three weeks on the trot than getting a writeable CD drive on your computer.

And we haven't even mentioned Tempest protection!

Paranoid they may been, thorough they certainly were.