THE UPSTAIRS BOX
I would be in utter bliss if everything just stayed where I put it. But that wouldn't be any fun at all, would it? If that happened, legos would never become guns defending us against the lions in the jungle/back garden, bouncy balls wouldn't get to play hide and seek, and two very active boys wouldn't get to spontaneously shed their socks to run barefoot in the grass.
Hence the upstairs box. Things I run across go into the box, and we as a family empty the box when we go upstairs. I've heard other people say they have a box for each family member, but right now we just use one big one. So far it's working, and I don't really have a place for 5 different boxes, but we may move to that system in the future.
Another reason this works for us is that we live in a three story house, and while I like to reap the benefits of a built-in stairmaster, I don't have the time or energy to run up all those narrow European stairs hundreds of times a day.
The Upstairs Box. It's practical, efficient, and it works for me.