Hourglass - Hourglass is the most advanced simple countdown timer for Windows.
Free Countdown Timer - Free Countdown Timer is a free, full-featured and user-friendly countdown timer for Windows
Be Focused by XWaveSoft - Simple Pomodoro timer in your Mac's menu bar
XNote Stopwatch - Try the most feature-rich stopwatch and timer software on the net for free!
Gestimer - For those little reminders during the day
Flow - Stop managing projects from your inbox.