Lock Mac mini but keep secondary display running I am configuring a dashboard on a TV display to show latest sales stats, etc. and am running this off our existing build 'server', a Mac mini. The Mac mini is connected to a standard monitor and a TV using AppleTV. What I'm after is a way to keep the Mac mini running in the background, with the standard monitor, USB keyboard and mouse disabled but to keep the main TV on showing a chrome browser with our dashboard app in it. 

I'm pretty sure I'm asking for something impossible but I wondered if anyone had any suggestions?
I would use status board and an old iOS device to run the status board, but perhaps that's not the suggestion you are hoping to get. OS X doesn't allow one screen to opt out of locking - the current user is all or none in terms of keyboard input. 

You could also develop custom kiosk software. But I've only seen that lock all the screens - not one.