I'm looking for a GUI utility which you can use to set a timer to go off after a fixed amount of time. When it goes off there some sort of strong visual notification.
Required features:
- Works on Linux
- Works on x86_64 machines
- Works with X windows
- Gratis
- Small size
- Uses very little system resources
Desired features:
- Ability to set a message which pops up when the time is up
- Audio notification in addition to the visual one
- Option for "XYZ minutes left" notifications
- Taskbar indicator for amount of time left
- Allows setting an alarm for a fixed date and time rather than a timer for an interval
- Stopwatch
- Libre software
- Not too ugly or tacky (I know this is subjective)
- Can match desktop environment theme