KeePassXC or keepass2, VLC, mplayer, mpv, qmmp, gimp, qtqr
on X: xdotool, xmacro
on Wayland: ydotool
free cool games (some not in repos, some snaps): OpenTyrian, AstroMenace, warzone2100, Card-Forge Java MTG Simulator, Heroes Forge, Spiral Knights (Very old; May need Java 64bit tinkering; Also on Steam)
It’s quite helpful if you have a big monitor and play games that have textures similar to the cursor colors. On Gnome it’s available as an extension (Wiggle)