I use a software program called multi-track stopwatch. It's a simple computer program that has 10 different stopwatches. You can set each one individually and time independently. What I do is set one to count down from half hour, one to count down at intermission(s), and then one to count up for each act, one for show time, one for run time. It may seem excessive but it's time to do the report at night you just read right off your screen. Best of all it's free!