I keep an eye on vixra.org. Another site I keep an eye on is unz.com. They are an odd couple, and might seem to have nothing in common, except that both were founded by physicists (Phil Gibbs, Ron Unz).
But both serve as a source of shunned news and views. Vixra, of course, started life as a haven for physics papers that were kept off the arxiv. Unz.com, meanwhile, is "A Collection of Interesting, Important, and Controversial Perspectives Largely Excluded from the American Mainstream Media". The powers have no interest in Vixra, it is left to sink or swim on its own, but Unz.com carries material that is considered genuinely dangerous (mostly from the right, but also from the left), and I would be unsurprised to wake up one day and find that it has been taken down by some politically motivated campaign.