Ok, I found this image while surfing the wild web and thought I had to share. I don’t know the background, but it definitely is the sort of thing we used to rely upon in D&D.
This reminds me of the “Scarab of Death” from 2nd edition. This was a cursed item that when you picked it up, turned into a living scarab that burrowed into your flesh and straight to your heart, killing you. Your only option if you picked it up was to cut off the offending limb and hope you stopped it in time. It was activated by body heat, so if you were one of those players who read every rule book cover to cover (i.e. me) then you never picked up any scarab unless using tongs. But, being the resourceful players we were, we transformed this death bug into a pretty decent weapon. First, we had a spear tip custom made by the local blacksmith with a shallow oval recess in the center that would accommodate the scarab. Then we mounted the scarab very carefully, and then wrapped it with cloth to hold it in place. Use red silk for that special touch! Now, when in battle, we would stab someone with the “Spear of Death.” Upon a successful hit, the scarab would react to their body temperature and burrow to their heart. Recover after battle, clean and reuse. Tada!
I think the granddaddy of all of this inventiveness was James Ward’s article Notes from a Semi-Successful D&D Player (Dragon #7), which extolled the virtues of the 10 foot pole (or, if your DM loved 10 foot corridors, the 12 foot pole). I never went anywhere without my collapsible 12 foot pole thereafter! Other tricks were the sharpened coin sewn into my cuff, and the garrotte sewn into another cuff, and various blades secreted about my person. I played thieves; can you tell?