https://filestr.vercel.app/ has previews for image, audio and video files so far. Would be cool to implement PDF previews, use Threejs for rendering 3D files, etc. I plan to make it easy in Habla to embed these files as nostr references. NIP-51 is really interesting since it allows you to create lists of file events which could be rendered as a gallery. These files and lists can be zapped, commented, bookmarked..