And I've mentioned it elsewhere on here before, so sorry for the repeat.
Keys! We have a hook right inside our door for my keys, another for hats and what-have-you, and a third for hub's keys. He never uses his hook and is always losing them. I, however, like many other things, have a system: I walk in, immediately hang up my keys and my purse (that goes on the bannister), and then they are ALWAYS there when I need to leave again.
Brilliantly simple, and simply brilliant, no?