I have a very short memory so it's good that I spend my days flitting from one subject to another for work. I do tend to lose my wallet a few times a day though. Mostly it's because the wife likes to put stuff on top of it. I think she is trying to drive me insane so she can have me committed and have full access to the remote for watching all those chick flicks she likes. I don’t go anywhere other the than the store and home so I don’t really have the chance to lose my keys.
I leave the key in the car locked in the garage, but I do take them out on occasion and promptly lose them. A dude has created a very simple and geeky way to keep up with all his keys using those green rectangles you plug your LEGO bricks onto, some eyehooks, and various LEGO bricks. The dude took the standard 2 x 4 LEGO bricks and screwed an eyehook into each brick.
The dude then took wire ties and hooked the keys to the eyehooks. The result looks like a cobbled together mess unless you are into that style, but I don't see why you couldn't just run those eyehooks through your normal key ring. The end result is that the dude can walk in the house, press the LEGO onto the green base plates, and hang his keys by the door.