A common electronic security technique involves a rolling code sequence where the key changes everytime it is used. The key is one of a series that must be used in order.

Some folks have trouble remembering just one PIN but for the rest of us we could probably manage a double PIN.

So for each card there are two pins but the system will only accept the one not used last.

If a thief memorises you card at the ATM or supermarket checkout whatever he cant steal your card and use it because the alternate number is now the expected one.

If you find one number does not work, probably because you forgot which one you used last time, just use the other one.
-- KiwiJohn, Dec 05 2003

Small piece of paper with 3 4-digit numbers written on it. http://www.halfbake...20written_20on_20it
The same idea, but more clever. [Overpanic, Oct 04 2004]

Panic PIN http://www.halfbake...om/idea/Panic_20PIN
A much better security device. [Overpanic, Oct 04 2004]

The problem here, as it has been pointed out multiple times [see annotations in links], is that ATM cards are generally not "stolen", for the exact reason that it is too hard to find out someone's PIN. The most common scenario is that someone will be held up at an ATM right after they've inserted their card, so the thief just instructs the person to enter their PIN for them. That's of course, where the Panic PIN comes in handy...which, by the way, if you haven't noticed, is the most popular idea on the HB.
-- Overpanic, Dec 05 2003


Are you sure that my wife can't smack me upside the head with it?
-- 2 fries shy of a happy meal, Dec 05 2003


Yeah, Overpanic, but then the thief will just wait to hold you up until you walk away from the ATM with the cash, as has also been mentioned several times in the Panic PIN (which hasn't had much effect on the mob mentality over there that somehow still thinks it's a good idea).
-- oxen crossing, Dec 05 2003


I don't know about you, [oxen], but I don't generally take large sums of money out of the ATM at one time. Maybe $100? It doesn't seem that profitable to me.
-- Overpanic, Dec 05 2003


Yeah, it is. I pulled one off a bus a few years ago. He was seen leaving the apt. building I lived in as I was parking. I sez to myself, I sez "S'picious lookin' feller" - went upstairs - Landlord's door was off the frame. Back in the car I went, and down the road I went. At nearest bus stop - thar he wuz - sorta had my landlord's cheapie stereo in his big-ass bag. He's doing 5-10 yrs., with at least 1 to go as of this writing. So, yeah - $100 bucks is a windfall.
-- thumbwax, Dec 06 2003


define: sorta
-- po, Dec 06 2003


I was being kind.
-- thumbwax, Dec 06 2003


That's all fine and good, but $100 isn't as much as a windfall for me as $500 is. So if something is in place that will dissuade individuals from thieving me at the ATM machine, where they could get as much as $500 at one time, I've saved $400.
-- Overpanic, Dec 06 2003


When it comes to getting held up, I no longer care about the money. I just don't want to get clobbered over the head with a baseball bat for any amount of money, and none of these _______ - PIN schemes are going to do anything about that.
-- oxen crossing, Dec 06 2003


Yeah, that's why you need a PIN knife. A safety PIN just isn't going to cut it.
-- thumbwax, Dec 06 2003



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