Overlooked Tools: 'at'

If you find you are using commands like sleep to run a one-off task at a specific time, then meet the GNU at command.

at will allow you to specify a time to run a specific command, and accepts a wide range of different formats including “now + 4 hours”, “noon”, and “next tuesday”. The command will read commands from stdin or using the -f to specifiy a file to be executed using the default /bin/sh.