i was just browsing through....
a note to the person above me, hotglue wouldnt work, metal doesnt stick with hot glue almost at all...as soon as there was a sharp tug they would fall off
if you really wanna make it permanent (forever forever, no trading) use e6000 jewelry adhesive, and even then, dont rip at them (metal isnt porous so glue resists, and the rubber backs are a type of silicon, which again, nothing sticks too...)
I keep all my pins in bags or books, the lanyards itchy me
annnnd one last thought, to the OP:
everyone holds different pins at different values, and some that you have may appreciate in actual value over time, but not really by much...if you want a *rare* or *valuable* pin, look specifically for LE pins (sets of under 2000 are the best)