Cisco Catalyst 6509 (1999)
Ask just about any network admin what the mainstay of a large corporate LAN is, and they'll answer the Cisco 6509. At a decade old, original 6509s can still be found in datacenters the world over, doing everything from large port aggregation to operating as the core of enormous switched networks. Options abound with firewalling, WAN, IDS, VoIP, PoE, gigabit copper, fiber, and 10G support. In many cases, original 6509 chassis have had significant performance and feature upgrades without ever leaving the rack, thanks to the highly expandable nature of the design. It's the big switch that could, and still does.