We called them "luggables". They're expensive, but having a server in a box with a monitor was worth it when you could lug it to a customer site and give a live demo of your server stuff. We were doing telephony stuff and you could put a $5000 dialogic pcie card in it and demonstrate call handling live. We can do that with software on a standard issue laptop these days, but the luggable helped seal the deal back in 2005.