EyeRest
A lightweight Windows tray application for the 20–20–20 rule
...Users can configure how often reminders appear, how long breaks should last, and define quiet hours when reminders are paused — making it adaptable for both focused work and creative sessions. EyeRest typically includes motivational or instructional content during breaks to reinforce good ergonomics, promoting reduced eye strain, improved focus, and overall wellness for anyone who spends extended periods at a computer.