How do you handle timekeeping?

The standard Windows software clock can be considerably inaccurate. There are several ways to synchronize one's computer to standard time (see subsequent question). However, most of these ways require continuous access to the internet, which may not be the case at many school sites and in developing nations. The detection of SIDs and sharing of subsequent data does not require extreme clock accuracy, so the monitors can still be used in areas without internet access. However, techniques are available for those sites interested in keeping a very accurate clock (see below).