Virtual MIDI input device? Can I create a virtual MIDI keyboard that plays a .mid file?

I have the Piano VST Addictive Keys, and would like to be able to play .mid files using the sounds that this VST provides.

I thought I could use a virtual midi device as the input device for Addictive Keys.
The easiest way to play a MIDI file with a VST plugin is to load it in some VST host (see here for a random list).

If you want to use a virtual MIDI port, you can create one with the IAC driver.