Silicone sealant, $3.99

The maxim treat others as you would like to be treated has applications right across a person's life,  including their approach to op shops. I am wary of what I donate to op shops because I don't want to be burdening a charity with the cost of disposing of unsaleable goods. And yet, I buy a lot of things from op shops that could easily be classified as rubbish, such as half-empty tubes of silicone sealant. So I feel justified in donating the antennas off my now-redundant wireless modem to my local op shop. Those little black sticks may well pose a mystery to the ladies unpacking my box; but then, that's what they have a "What is it?" shelf for.