Networking equipment is another place where 64-bit systems are useful. See chip offerings from places like NetLogic and Cavium, for instance: their multicore M

Networking equipment is another place where 64-bit systems are useful. See chip offerings from places like NetLogic and Cavium, for instance: their multicore MIPS chips are 64-bit. Databases are another place where 64-bit systems shine. Maybe you already assumed that was included under "HPC-type applications", though. When I hear HPC, I think number-crunching, not databases, though.