A legacy peer-to-peer LAN operating system for DOS, Windows and OS/2 from Linktivity, Tucson, AZ (www.linktivity.com). It supports Ethernet, ARCNET and Token Ring adapters as well as its own twisted-pair adapter at 2 Mbps. LANtastic was popular in the DOS world and in mixed DOS and early Windows environments. Although LANtastic may still be purchased, Linktivity has ceased further development of the product.