Earlier this morning I needed to whip up some time delayed action on one of my servers. This is normally something I would just drop into a crontab and kind of you know forget about. Honestly I love my crontabs but they can become rather unwieldy once you exceed a screen of entries especially if you have any sort of complex time signatures.
In addition when you want to simply delay the execute of a script for a short period of time setting up additional cron jobs can be slightly burdensome especially for these sorts of egg timer situations. You have to remember to cleanup your crontabs regularly. I am already exporting a few handy convenience environment variables for creating egg timer scripts in my .bash_login for example: