It's not as functional as these but couple of years ago I quickly coded a timer for Windows - https://code.google.com/p/fst/ - "Freakin' Simple Timer for Pomodoro Technique"
You quickly enter time such as "30m" and it'll ping you when time is up, you can optionally enter a reminder text as well.
You quickly enter time such as "30m" and it'll ping you when time is up, you can optionally enter a reminder text as well.