To make it easy to see the most popular, please post a single option per comment. Upvote the ones you like. I'd love to know which are the best.
TMSU: TMSU is a command-line tool for tagging your files. It provides a simple command-line utility for applying tags and a virtual filesystem to give you a tag-based view of your files. TMSU is suitable for users who are comfortable working in the terminal.
I've been using tmsu for years to manage thousands of pdfs and images for my academic research.
Dolphin File Manager: Dolphin is the default file manager of the KDE Plasma Desktop Environment and offers a built-in file tagging feature. You can tag files into categories irrespective of their location, which gives you a new way to organize your files.
Note that the tag functionality only works if you also use Baloo, their file indexer.
TagSpaces: TagSpaces is a privacy-aware file manager with tagging and note-taking capabilities. It offers a consistent user experience for organizing and annotating files across Windows, macOS, Linux, and Android platforms. It allows you to add tags and descriptions to files and folders, making it easier to search and organize your data.
Supertag: Supertag is a tag-based filesystem written in Rust for Linux and macOS. It provides a tag-based view of your files by removing the distinction between directories and tags. Supertag is still in development and may not be suitable for all use cases.
Tagsistant: Tagsistant is a tag-based filesystem for Linux that turns directories into tags and searches your files for you. It allows you to create tags, tag files, and search for files based on tags.
What features do you expect from a tag based file manager?
I ask because Emacs Dired might qualify. It allows you to apply arbitrary "marks" to files, each mark is a single character. Some characters have special meaning, e.g. "
D" means ready for deletion, and "*" is the default mark (not for deletion). You can then preform batch operations on marks, for example using marked files as arguments to a shell command.However, without additional extensions, marks are not persisted between sessions, there is no virtual filesystem, and no search function for listing all files across multiple separate directories that match particular tags.
One such extension is filetags.el which is an Emacs UI inspired by the filetags file manager (which someone else already mentioned).
