Accubattery - Monitor's battery capacity through the use of science
Padbury Clock Screensaver - Minimal screensaver for Mac
BatteryCare - BatteryCare - Application and good practice guide for maintaining and optimizing the battery of the modern laptop
Aerial - A beautiful aerial screensaver for your Mac
coconutBattery - With coconutBattery you are always aware of your current battery health. It shows you live information about the battery in your Mac and iOS devices (iPhone, iPad)
Fliqlo Screensaver - A screensaver that displays the time using a flip clock.