The docs say: "The Cisco Catalyst 4500 Series Supervisor Engine II-Plus-TS includes a dedicated 10/100 copper RJ-45 management port located on the supervisor faceplate for disaster recovery. If all the flash storage devices local to the switch are corrupted or completely full, the supervisor engine can download an image from a Trivial File Transfer Protocol (TFTP) server within seconds, minimizing network disruptions."
How does that work in practical terms? If it's something you configure in config, you'd think it'd get blown away when the flash memory pukes.