function to return most recently modified file to command line

[Eric Smith <es@xxxxxxxxxxxx>]

I would like to have a function ideally to bind to a key combination
that returns the most recent file to the command line.

Like I might type
$ acroread <Alt-B>

would give

$ acroread todays_news.pdf

A couple of nice extra features would be:
Specify the type of file say `pdf' or `txt' for the latest instance
of that type of file.
Also the function could automatically add an <enter> after returning the
filename.

thanx!

-- 
Eric Smith