Parental time control app Timekpr has been revived and provides parents with an easy way to limit their kids' computer time.
Kettle's on! Pizza's in the oven! Only 23 minutes until a new episode of Inspector Spacetime - all are situations where keeping an eye on the time is important. Now hopefully you're not like me (i.e. useless at doing so) but, should you be, then TeaTime is a neat Unity-launcher based alarm applet that works wonders.
Some of the most useful applications are often borne out of a personal need. Such as this 'Tea Time' application created specifically for Ubuntu Unity by rojtberg. With Unity lacking support for 'traditional gnome applets', rojtberg had to find a different application. There are 'indicator timers' available - such as this one - but this wasn't ideal for him.
"Getting things done" is, of late, a phrase alien to my work ethic. Rooting around for ways to help my concentrate I remember the 'Pomodoro Technique' - a time-management method that is, supposedly, meant to help. And thankfully there's an app for it.