Can't resist sharing this unhelpful information:
Pins are not just for holding pieces of cloth together. At least in Ankh-Morpork pins are something worth collecting. In this city over twenty-seven million pins are produced per year by the combined workshops called pinneries. Among them are specials like wax-headed, steels, or silver-headed. Lapel pins, or blazons , do not count since they are not true pins. Mere needles are looked down upon as just faux-pins with a hole knocked through one end. Nails cause strife: Dave refuses to have them in the shop, citing as his reason the fact that some collectors are young boys, thank you very much. The collectors of pins call themselves pinheads. A great number of magazines on pins exist with titles like Pins Monthly , Popular Needles , or Total Pins . The specialist shop to go to for all things acuphile is Dave's Pin Exchange, on Dolly Street. The collecting of pins has decreased greatly since the collecting of stamps has caught on. The details on pins are revealed in Going Postal