Go Take A Hike!
Hot 10 . . .
is it what I want the most, and can I own it? Or is it what I talk about the most, or what burns the hottest?
Because of all the board game components I can think of, rubber would burn hotter than anything else. unless there's some game out there with magnesium shavings or gasoline.
It has no particular set purpose. Everyone uses it for whatever they feel "hot" means.