The best replacement for screensaver is wallpaper.

The best alternatives to screensaver are rated as following:
★★★★★  wallpaper
★★  sleep mode
★★  turn off monitor
★  wallpapers
★  display sleep
★  screensaver

Your alternative for screensaver is not listed? Suggest!
Speaking about screensaver, one probably shouldn't forget about password mac.

Other search terms related to screensaver and their ratings are:
★★★★★ password mac
You have in mind a companion for screensaver and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of screensaver in all years. Click on graph for more.
screensaver
wallpaper
sleep mode