They smell good.
They are durable.
They're common place enough to be ignored.
People do all sorts of things with them. They are a great case for electronic projects. They're storing my little screwdrivers. They stored my Lottery tickets for a while until the Powerball got greedy and raised the price. I felt stupid throwing away $40 a month on tickets for the "Math Tax".
Now I've heard a new use for the thing - as a wallet.
Ok, sure, it sounds kind of low rent, but it offers an interesting benefit. They will shield your credit cards from being read by RFID readers.
I'm not a fan of RFID. The chips work a bit too well. It is a little electronic chip that sits inside credit cards and ATM cards that you waggle in front of a reader and under normal conditions can only be read within a few feet.
That's Normal Conditions. Since RFID is protecting your credit limit on the credit card I feel safer without it.
Sure, this is "Tinfoil Hat Territory" but if I get a card with a chip in it, I immediately contact the vendor for a chipless card. The old school magnetic stripe is good enough for me.
If I can't get the new card, I find where the little square chip is in the card, then hit the chip with a hammer and a "punch". Electronics can be fragile and that "disables" the chip so I can be completely comfortable.
I tried it out with a card that I did not activate because it has a chip in it and it fit easily inside of an Altoids tin leaving room for some (*GASP*) cash and other things I may find I need. Like in this Lifehacker article, you even may have room for a memory stick, and you can keep a mugger wallet in case you are in a questionable neighborhood.
You know, a couple bucks and some old spent gift cards kept as a decoy.
I'm just amused enough at this little hack to consider it. The little tins are just "too nice to throw away" and I have a few here.
Or just stuff your cash in your sock. I won't tell.