TClock Light - TClock allows you to modify the clock on the taskbar in Windows.
TimeLeft - TimeLeft is a versatile desktop utility - it can be used as a countdown clock, reminder, clock...
T-Clock Redux - T-Clock Redux in an enhanced fork of Stoic Joker's T-Clock 2010 with ISO week number support...
Hourglass - Hourglass is the most advanced simple countdown timer for Windows.
DS Clock - Keep your time synchronized with Atomic Time servers, using customizable digital desktop clock with westminster chimes.
wnr - Better than pomodoro, this timer app balances work and rest.