Visible beams of light from sun lamp

I am trying to make my render look very antique, so I want there to be visible beams of light coming in from the direction of the sun. Nothing too heavy, just some obvious beams. How do I do this? Thanks!

GIMP or Photoshop maybe?

you could a spot light with halo that would show volumetric light
and you would see the beam of light that way

check wiki page for volumetric light