When selecting the port for a new printer in Windows you can pick LPT1, COM2, etc. There's a FILE: option that does a "Print to File" (it's been around for many versions of Windows).
I see on my Win8 system that there's a new port called "PORTPROMPT:" that I never noticed before. I can't seem to find any documentation about it. What's it do differently than the old FILE: option?