Easy Tip to Avoid Accidently Erasing Memory Cards

I have a tendency to carry a lot (and I mean A LOT) of memory cards on a shoot.  Between shooting panoramic photos, time-lapse sequences, and HD video, I burn through memory cards faster than most.  I find myself needing to be certain that I avoid accidentally erasing data.
Here’s my strategy for safety:

• Make sure that all memory cards are erased BEFORE going into the field.  Don’t bring cards with data or you’ll sit there wondering if you transferred them already or if you’re about to wipe your only copy.
• Have two card wallets.  One full and one empty.  Make sure they have the same number of slots.
• Put the full wallet with all of the blank memory cards into your right pocket.
• Put the empty wallet with no cards in it in your left pocket.
• As you shoot cards, place them upside down in the card wallet in your left pocket.
• Repeat this phrase ten times… The cards in the right pocket are the right cards to shoot with; the cards in my left pocket should be left alone.