Rackmount networking hardware (routers, switches), disk arrays/storage appliances, etc. I work with a lot of equipment that does. It's usually a rj-45 connector

Rackmount networking hardware (routers, switches), disk arrays/storage appliances, etc. I work with a lot of equipment that does. It's usually a rj-45 connector on the hardware, but you just use a cable that has rs-232 on one end and rj-45 on the other. The fact that this has an actual rs-232 port makes it really tempting for me to buy one!