This is waaaay too late a post, but still...

I actually wrote an application that partially does what this request wants, that is, using specific keys to do something to files, making one-handed file-management a bit easier. Check out http://www.pneumatictubes.rapidstreams.net and look for the feature regarding "Conveyor Belt" (not the most imaginative thing to call it, I know  ;D)

If there is enough request for a closer solution to this I can probably accommodate this in a while, as it is a very handy idea.