“Ah, yes. I had had the same brain system failure that Chris described – staring at the ATM and just not remembering that PIN! So now I write the PIN number on the back of each card, in the signature box. WAIT! No, I don't write the actual PIN. I use one 'formula' for all cards. For example, a formula could be to add 3333 to the actual numbers of your PIN. The new TOTAL is then written on the card. If this was your formula, you only have to subtract 3333 from the PIN written on the back of any card, and you will have the actual PIN for that card. Now, does anybody remember where I left my wallet?” (A. John Gallant)