Krusader is an advanced twin panel (commander style) file manager for KDE Plasma and other desktops in the *nix world, similar to Midnight or Total Commander.
Unraid is software for storing and managing digital files on a mass-storage server. It is an embedded Network Attached Storage (NAS) server operating system.
Nextcloud is an open source, self-hosted file share and communication platform. Access and sync your files, contacts, calendars and communicate and collaborate across your devices.