The Datanet is a Space Pirate network mentioned in a scan in the Command Center of Agon Wastes in Metroid Prime 2: Echoes. It seems to be the Space Pirate equivalent of the Galactic Federation Database.
"Security Alert, all systems and units. Datanet has been compromised. The Hunter has hacked our datanet. All our secrets are now hers. She cannot be allowed to escape. Terminate her on sight!"