What are some alternatives?
When comparing Gnome Clocks and T-Clock Redux, you can also consider the following products
Free Alarm Clock - Free Alarm Clock is a free, full-featured and user-friendly computer alarm clock for Windows.
ClocX - ClocX - freeware analog clock for Windows desktop with many features like calendar, alarms, skins, antialiasing and transparency.
LClock - Longhorn systray clock program
Talalarmo - Minimalistic android alarm
TimeLeft - TimeLeft is a versatile desktop utility - it can be used as a countdown clock, reminder, clock...
KTimer - KTimer is a little tool to execute programs after some time.