time:calc is a time calculator that does conversions and calculations of time. It also works with timecode enabling calculations of frame rates for TV and film.
If you want to find out what 2 hours, 132 minutes and 223 seconds is then type in 2:132:223 and time:calc will give you back 4:15:43. Wow!
If the time is 10:36 and lunch is at 12:40, then type in 12:40:00 - 10:36:00 and time:calc will let you know you have exactly 2 hours and 4 minutes to go. Sensational!