Sometimes I run late. Late to meetings, late to go home, late to pick up kids... I know I'm not alone, too. So I fixed this problem with a handy little script I call "Procrastinators Friend". This script is pretty simple, it just sets your clock ahead by a random amount, between 5 and 15 minutes. I then set this up to run every hour, so I'll never quite know how fast my clock is running. In order to prevent this from going crazy, it also syncs up your time with a network time server before adjusting it, so you'll never be too fast or slow.
Naturally, the buyer should beware, here. System tools that rely on modification dates to do stuff will be thrown off by this little script. But maybe that's worth it to be on time, every time.
Use cron or launchd to run it regularly.
