Dropbox - Online Sync and File Sharing
Meta Search - Search your Desktop, Google Drive, Dropbox, Gmail, Evernote.
Syncthing - Syncthing replaces proprietary sync and cloud services with something open, trustworthy and...
Google Cloud Search - Search across all your company's content in G Suite.
Google Drive - Access and sync your files anywhere
Vaultedge - Access all your documents in one place.