Hourglass - Hourglass is the most advanced simple countdown timer for Windows.
wnr - Better than pomodoro, this timer app balances work and rest.
Online Stopwatch and Timers - Sometimes everybody need to count time for some reason.
Free Countdown Timer - Free Countdown Timer is a free, full-featured and user-friendly countdown timer for Windows
vClock - Web based time tools including Alarms, Timers, Stopwatch, and World Clocks. vClock is customizable and has a clean user interface.
Gestimer - For those little reminders during the day