Where do you leave the coin so that when you have no memory of where you put it, you can lay your hands on it at once?

You leave it taped to your hand.

Heh, this is pretty much how I live my life really. Coins go in the obvious coin place coz if I put 'em anywhere else I'll never remember where I put 'em.

See also: Proper Pocket Discipline. Everything that goes in pockets has an assigned pocket. No more searching for lighters! No more worry about keys scratching phone screens.

My books are in alphabetical order these days.

I suspect having a system for these things will also leave you better off if/when you go senile. If you've always looked in the same place for your coins for 60 years it'll be more ingraned.

Solved in 1876. :)

I'm sure variants of this can be used for other objects. For general-purpose living I've found that simply keeping a tidy living space helps immensely. I throw things out often.

Never, ever, let any other member of your family/living-group tidy your stuff up. That way a) you can remember where you put stuff and be right, and b) If you're wrong, you can only blame yourself, thus reducing group discord. :)

Unfortunately, if you live with people who don't think that the natural way to organise stuff is 'piled wherever I put it down' then this method can itself cause discord - you just can't win :(

My usual approach for finding something that wasn't where I looked for it is to trace back my path to the last place I clearly remember it being (for stuff you lost track of recently, which is most of the stuff I need to look for). The item is nearly always found somewhere in arm's reach of that path. I can't understand why the suggestion to use this method is not considered helpful by those I live with.

I don't think that you can organise everything so that it is always where you first look for it, short of an eidetic memory, but so long as nearly everything is where you remember putting it and most things that are not are found quickly, you're most of the way there.

I wouldn't be surprised if the technology to be able to google your stuff becomes available within the next decade or so, perhaps via databases created by object recognition, maybe of a life-log, or something? That'd be a good way to avoid doing a load of work forcing all your stuff into some systematic order.

For specific, special items, spend a few seconds thinking about the 'right' place for it. Then place the item there. If you ever need to find the item, repeat the same though process and there's a good chance you will again think of the same 'right' place. My problem isn't that I can't think of the place where it should be, but that it is very rare that I actually put it there.

However, I wonder if you were talking specifically about finding lost items, or just the general probIem of finding solutions to "foolish" problems. Then I suspect this will grow to be a long comment since I am simultaneously extremely absent-minded and also energetically solution-oriented, so I spend a lot time developing tailored solutions.

First, I'll discuss general principles of the 'systems' I use to solve these problems:

1. I invest energy in systems proportional to the degree there needs to be a system (e.g., measured in units of aggravation or resource costs). I don't develop systems just to have systems, since this is a failure mode for me.

2. Solution development is always a work in progress and I try to be laid-back about that. I'm always open to the possibility that a system is causing more trouble than it is worth. An imperfect system won't be further updated unless the energy expense makes sense (see 1). Sometimes a system seems to work fairly well, but then an extra dose of aggravation will motivate me to improve it.

3. Every problem might need its own unique solution, fitted for you and your lifestyle. Many systems are very nice in principle, but simply don't work in practice -- usually due to inability of me or family members to maintain the system. That is, a 'good' system is one that actually works.

Next, I'll list some of the solutions that I've found so far or need help with:

• Solution: A lockbox for the key. I was always trying to find my keys. Leaving in the morning, usually in a hurry, there were several places I had to look -- in any pair of pants I might have worn, in any jacket pockets, on the actual key ring where they were supposed to be (fat chance), or in the junk drawer where I tend to empty my pockets when I come home. Looking in even just these three spots was too aggravating and there was no solution until I started keeping my keys in a lockbox outside my house. The key always makes it back in the lockbox when I come home, so when I leave in the morning, I can just leave -- no worries about the key! This is greatly helped by the fact that I have security code to open my car, I don't need to carry a key for that either.

• Solution needed: I don't have a system yet for ID cards and debit cards. Every once in a while, I end up with two copies of one (for example, if I lose it, get a replacement and then find the old one) and then that system is stable for quite a while because I'll keep one at home and one in the car. However, I never have the cards I need when I'm traveling with my husband or walking somewhere. The only exception is the library card, which I keep in our "book bag".

• One day a week for the library. If we go to the library irregularly, we never remember to return books and we ended up paying hundreds of dollars in fines last year. Since this was obviously a significant resource drain, we had to decide if going to the library was important. (For example, we decided renting Redbox movies was not important since we had the same story there.) Since going to the library was important to us, we now go every week on a particular day. Before we go, I walk around the house and collect anything that looks like a library book, and then (fortunately) the library also e-mails me if we miss one and I'll know to spend extra time looking for that one.

• Keep children's socks right by the dryer. I have a drawer in the laundry room for my kid's socks. This seems to be the best way to get them in one place. An initial phase of the solution was to begin with very many identical pairs to save time on matching, but then we got too many different kinds of socks from cousins (hand me downs) and I gave up on that.

There needs to be some constraint on "hidden". Otherwise I just put it in the mailbox or wherever I'm in the habit of looking everyday.

Maybe how I'd tweak it is have a requirement that an average third-party will find it in greater than 15 minutes.

So what are the -2 points for folks?

I'm confused about the "hide" part of the initial task, or the "fooling" that needs to be unfooled. The objective function rewards ineffective fooling.

It seems you simply mean "store" such that you can find it.