Over the years I suppose I have bought lots of stuff, mostly furniture, that needed some assembly.  You know the stuff.  Comes with little wrenches and inscrutable instructions is several languages.  I have been tossing the little wrenches in a box (in case I ever need them).  Not sure how many I have now.  I should probably throw these out since I have multiple full sets of metric and US wrenches these days.  And most of the furniture I assembled with these over the decades is probably long gone.