Running variable commands from psql

Is there a way to pass a psql variable into a \! command in psql, e.g.:

    test=> \set x ls
    test=> \! :x
    :x: not found

I specifically want the currently connected database name to be passed
to a \! command.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +