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.
Keypirinha - A lightning fast and flexible keystroke launcher for Windows. No installation required (portable).
Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
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.
Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.
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 .
Strikethru - Strikethru is a kind of to-do list notebook for managing work lists and staying updated with the important tasks.