iStat Menus - "An advanced Mac system monitor for your menubar."
Wallcat - Enjoy a new, beautiful wallpaper, every day.
Stats - Simple macOS system monitor in your menu bar.
Splashify - Beautiful desktop wallpapers for Mac and Windows
MenuBar Stats - Advanced Mac system monitor right from the menu bar
Irvue - (previously Unsplash Wallpaper) Gorgeous wallpapers on your Mac.