Best way to dispose of a USB flash drive?

October 2, 2008 2:22 PM

What's the best way to dispose of a USB flash drive?

Having recently upgraded the HDD in my laptop and my flash drive, I wanted to be sure to dispose of both in the safest manner possible. I've decided to have my HDD mechanically shredded (at a cost of about $5), but I'm not sure what to do with my flash drive. I know the "smack it with a hammer" technique is one option available to me, but should I look into others? Is shredding an option, or using some type of software to wipe the drive clean?

posted by brandman to computers & internet (14 comments total)

At the risk of being unhelpful, why dispose of it at all? What's wrong with having two flash drives? And why not put the old HDD into an enclosure to use for backups? Unless they're broken there's no need to dispose of them.

At any rate, unlike hard rives, there's no residual data signature on flash drives. Doing a complete format should be sufficient to remove all traces of data. On Linux using dd to write zeros to the device is sufficient. And any drive-wiping tool will do; Google points to "KillDisk" and "WipeDrive". But just formatting should be sufficient (note: not a "quick" format, but an old-fashioned format-every-sector format).
posted by GuyZero at 2:34 PM on October 2, 2008

Grill it or put it in the microwave.

Or just format it.
posted by fire&wings at 2:36 PM on October 2, 2008

I saw an instructable about making your own fimo casing for a USB drive which included baking the whole thing (fimo+usb drive) in the oven without ill effects to the drive, so don't assume a bit of heat will be enough.
posted by bjrn at 2:38 PM on October 2, 2008

Both seem like overkill unless you have actual secret data.

Hard drives have cool bits inside, like ridiculously powerful little magnets. I would open up the hard drive to remove said cool bits; you might have to fuck up the platters to get the out, but that's a good thing!

If you are actually concerned that someone is going to root through your garbage, recognize bent-up HD platters as such, fish them out, restraighten them, reassemble them into a new drive, and then go through the trouble and expense to try to extract usable information, and your name is not National Security Agency, then you might think about seeing a shrink.

I would smash a USB drive with a hammer if I wanted to nuke the site from orbit. If I were very paranoid or wanted an excuse to play with it, thermite is cheap and seems entertaining. At that point, you might as well use the thermite on your hard drive too. And anything that needs destroyin'. And some things that don't.
posted by ROU_Xenophobe at 2:40 PM on October 2, 2008 [1 favorite has favorites]

Thanks for the replies! A few comments:

Guyzero: I have another external HDD, so I thought I'd just get rid of my old internal one (it's got a few years on it, and I know mechanicals can fail due to age/use, so I didn't want to rely on it for anything worth backing up). As for the flash drive...I guess it's kind of the same thing, no reason to have a second one, and the size is small enough (256 MB) where it wasn't going to be very useful for backing up the stuff I wanted to back up.

ROU_Xenophobe: Guilty as charged...I'm a little paranoid about this stuff, and while I don't have government secrets or anything like that on my drives, I do have personal financial data and whatnot. So yeah, I'm probably a bit paranoid, but I figured a few bucks and/or a few minutes of time wasn't going to set me back too far, and it would give me a little peace of mind!
posted by brandman at 2:50 PM on October 2, 2008

Kill it with fire?
posted by InsanePenguin at 2:55 PM on October 2, 2008

Physical destruction is totally unnecessary. Overwrite both drives with random junk; even one pass is sufficient, unless your enemies are the NSA.

(conventional wisdom says three passes, but I saw a paper recently that showed this was complete overkill.. can't remember the title of the paper now, tho... check Schneier's blog)
posted by qxntpqbbbqxl at 3:40 PM on October 2, 2008

The three-passes wisdom was based on having an underlying magnetic medium that still had some residual magnetization. Solid-state devices don't work like this. One pass and it's gone for good (assuming we're talking NAND flash memory here).
posted by GuyZero at 4:01 PM on October 2, 2008

GuyZero, there is probably some residual charge in an erased FLASH cell. These slides [pdf] seem to confirm. Programming the cell to 0 and then erasing it again should eliminate any residual charge, though. And modern multilevel memories probably add another level of complexity. I've heard speculation that memory cells which have the same state for a long time might cause detectable physical changes in the chip (like electromigration, though probably not that exact effect). This is all definitely an NSA level of effort, though.

In any plausible scenario, after all, "They" will just break into your house and read the data off the drive you didn't erase.
posted by hattifattener at 8:41 PM on October 2, 2008

Why don't you give one or both to a tech geeky friend? I know that I'd love to be given a harddrive or flash drive, no matter how small. I'm always collecting flash drives of all sizes, no matter how small.
posted by Geppp at 9:08 PM on October 2, 2008

Mr Drive? Meet Mr Hammer.
posted by Mephisto at 10:01 PM on October 2, 2008

I'd stash it in the car or some bag I use now and then. Sure I have a nice flash drive, but just this week I was out and about and wishing I had one on me. I now have a nice tiny one clipped to my keys. Yes, I know I'm a dork.
posted by advicepig at 7:30 AM on October 3, 2008

While you're having the HD "mechanically shredded", why not throw in the flash drive?
posted by attercoppe at 12:32 PM on October 3, 2008

Late-breaking update to an old question, in case anyone happens to search AskMe and comes across this...I've donated my old flash drive to Inveneo.org. Per the website, "Inveneo creates highly sustainable and affordable ICT infrastructure technologies designed specifically for organizations that provide vital services -- education, healthcare, economic development -- in remote and rural areas in the developing world."
posted by brandman at 1:50 PM on January 27