Several years ago I read (and reported here on) a book called "The Big
Bang Never Happened". The author challenged conventional theories about
the formation and evolution of the universe. He proposed that large
scale dynamics were dominated by electromagnetic interactions rather
than gravitational ones. He had some pictures of plasmas which resembled
the shapes of galaxies, with spirals, etc.
Most theories that totally contradict the conventional wisdom turn out to
be wrong, so this one probably is, too. But Robin's comment about the
possibility of very large scale, strong magnetic fields reminded me of
this earlier theory. There are a lot of things which cosmologistsy can't
explain, so the door is not yet closed on alternatives.
Hal