It was interested to read this article by Ed Hooper, the author of a book entitled The River. Published in 1999, this weighty tome presented an alternative hypothesis for the development of AIDS, suggesting that use of simian organs during the early trials of the polio vaccine provided a pathway for the SIV virus to make the leap to humans, where it became HIV.
The hypothesis generated quite a lot of interest at the time, but faded into relative obscurity as many mainstream scientists decided that the pathway was more likely have been something to do with bushmeat. However, Hooper continued to promote his ideas and was he was recently given a boost, albeit an inadvertent one, when a paper by some proponents of the bushmeat hypothesis accepted that the HIV epidemic took off in 1960 in Kinshasa, or Leopoldville as it was then known. While the paper suggested that this change of pace was due to poor procedures in local STD clinics, Hooper has pointed out that the fact that there is no empirical evidence of HIV anywhere in the world before 1959 and the fact that Kinshasa was the centre of the polio vaccine trials is actually strong evidence to support his hypothesis.
I have no particular horse to back in this race, but Hooper's tale of a scientific establishment standing in the way of scientific progress and of computer simulations trumping empirical evidence is all rather familiar, as is the story of the Guardian censoring Hooper in its comment threads.
You could do much worse than to take a look.