Although an old thread, take a look at the Kensington USB remote. Its really nice. The USB dongle slips in to the remote when not in use, so you only have one item to keep track of, not two. It has forward, backward and black screen toggle ("B" key) buttons that function without drivers with both PowerPoint and KeyNote. Also has a red laser diode, is thinner than most others and runs on a slim lithium watch battery.
Much slicker and better looking than the Targus remote and much cheaper than the Logitech or Keyspan remote (though these provide mouse emulation that the Kensington does not).