I've got a standalone Linux-based PC for recording.
It boots linux (text mode) and immediately runs a script.
Hit R to record, S to stop. If you don't stop it goes for 6hrs, if you hit R again, it starts a new file. It uses a standard usb interface (M-audio duo) to record. You can also login with ssh to run remotely, or to get files. All files are timestamped, and accumulate on the hard drive (until I "harvest" them).
If you want a "headless" unit, I would just use a mouse as input, and rewire the buttons to footswitches or whatever. Use the keyboard LEDs to indicate the machine state -- recording, paused, or idle.
I've had great luck with a text-based linux machine. It is super reliable, and because it is text only, noone will mess with it. To the modern gui types It just looks like the machine failed to boot and it spitting out error messages!
Richard