Curling Brushes and "Picks"
I suppose most curling clubs are like ours. The club has some brushes that are available for people to use, but members are expected to get their own equipment after they have been members for a year. The brushes, at least at our club, are full of crud -- tonnes of gray dust that collects on them very quickly.
I have often wondered if the amount of crud that collects on our brushes might be reduced dramatically if we had a better filtration system for our ventilation and air circulation. I also speculated earlier that poor air filtration might have contributed to the poor ice conditions at the 2007 Tim Horton's Brier. I have no idea how much merit this speculation has, but my own brush sure seems to pick up a lot of crud awfully quickly at our club.