So years ago, when I still worked for somebody else, and we had to keep track of all of our billable hours, I created a personal timesheet/ billable hours tracker. It let me record my time in quarter hour increments by client, so come time to enter my time into the computer for the week, it was all there in front of me and I could enter my data in record time.So I had this idea the other day... why not create something like that to track light sources, magical effects, etc., in the dungeon. (I'm gearing up for a possible campaign where resource management will be pretty important).Each circle represents 1 hour of time, divided into 6 turns (6 pieces of hour pie). Every turn, the DM fills in a 1/6 segment of the pie for whatever's necessary (each torch or lantern, residual magic effects, etc.). It takes only a few seconds of real time for the DM to track the resources, and tell the players when it's time to burn one from their inventory.