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Listary is an excellent enhancement utility for list controls used everywhere: Windows Explorer, Task Manager, Registry Editor, and innumerable third-party applications.It searches folders, files or anything else as-you-type. Autocomplete, masks, hotkeys, regular expressions (pro version only) are good time-saving features.

Keypirinha is a fast launcher for keyboard ninjas on Windows.

FARR also lets you quickly run web searches, send email, manipulate files, control on-screen windows, and much more. Build and share custom commands or install plugins to add tons of new features, like live search features for your clipboard history and your internet bookmarks; a popup a calculator with history tape and persistant variables; and many more..

Quicksilver is a fast and free Mac OS X productivity application that gives you the power to control your Mac quickly and elegantly. Quicksilver learns your habits, making your everyday chores simple and efficient.

GNOME Do allows you to quickly search for many items present on your desktop or the web, and perform useful actions on those items.

Cerebro is an open source and free electron-based productivity software alternative to Alfred and Spotlight. It is focused on speed and good UI and UX. In most cases you don't even need to open another application, because you can see results right in Cerebro, like google maps, IMDV movies or contact details.

Lacona is a docker app for Mac OSX that accepts natural language commands. Call up Lacona with a keyboard shortcut and type whatever you want to do. It gives intelligent suggestions as you type and then follows your orders.

If you can see it, you can search it and share it from any device.Everything seen is remembered devices across all of your devices. Atlas pulls together all the threads of your digital life .Atlas Recall works with all the apps, websites, and services you love. No account authorizations required.Your digital life is more than just files. It’s the web pages, apps, emails, texts, chats, videos and more you use everyday. If you’ve seen it, you can search it with Atlas Recall

Hain is an ALT + SPACE launcher for Windows that looks and works similar to Alfred.

Spotlight is the system-wide desktop search feature built into Apple's OS X operating system since version 10.4 (Tiger). Backed by an index of all items and files on the system, it's designed to allow the user to quickly locate a wide variety of items on the computer, including documents, pictures, music, applications, and System Preferences. In addition, specific words in documents and in web pages in a web browser's history or bookmarks can be searched. It also allows the user to narrow down searches with file attributes (e.g. creation dates, modification dates, sizes, types) and, as of OS X 10.9, tags. Pre-installed plugins for the New Oxford American Dictionary and Calculator applications also included in OS X allow Spotlight to define words and evaluate mathematical expressions. »

Krunner is a multi-function command line menu for the KDE Plasma Desktop.At times, it almost seems as you could manage all your computing from Krunner. Among other things, you can launch commands, open websites using the abbreviations defined in System Settings > Shortcuts > Web Shortcuts, send emails, convert units of measurements, open particular system settings, and view the date and time.

* Ulauncher provides instant search results. It also remembers your previous choices and automatically selects the best option for you.* You can type in an application name without worrying about spelling. Ulauncher will figure out what you meant.* Improve your workflow with customizable shortcuts. Create shortcut for web search or your scripts.* Browse files and directories with ease. Type ~ or / to start. Press Alt+Enter to access an alt menu.