After a few years I still use Listary as my main search/launcher. It's very quick, has a very nice look and great system of filters and projects. There are problem with new version to be released, but I'm talking about version number 5.
Whisker menu - A menu that provides access to favorites, recently used, and searching installed applications.
Keypirinha - A lightning fast and flexible keystroke launcher for Windows. No installation required (portable).
GnoMenu - A consolidated menu for gnome that brings eye candy to the world of the Gnome menus.
Alfred - Alfred is an award-winning app for macOS which boosts your efficiency with hotkeys, keywords, text expansion and more. Search your Mac and the web, and be more productive with custom actions to control your Mac.
Streamlit - Turn python scripts into beautiful ML tools
Wox - An effective launcher for windows. A full-featured launcher, access programs and web contents as you type. Be more productive ever since. Wox is free for use and open-sourced at Github, Try it now! Download .