TimeLeft - TimeLeft is a versatile desktop utility - it can be used as a countdown clock, reminder, clock...
XNote Stopwatch - Try the most feature-rich stopwatch and timer software on the net for free!
Smart Sloth - Smart Sloth uses the concept of timeboxing, which is to allocate a set amount of time to each task, therefore, creating a deadline which can increase the productivity of the user.
Stopwatch - A Java countdown timer and stopwatch. Features a fullscreen and a resizable window mode.
ChirpyTime - ChirpyTime: Timer / Alarm Clock / Clock app for iPhone / iPod Touch
Dial - Quick & beautiful macOS timer.