shattered.io
The original home of SHAttered — the February 2017 research by Google and CWI Amsterdam that produced the first practical public SHA-1 collision, two different PDFs with the same hash. The paper and both colliding files are still downloadable, so you can check the hashes yourself. The site now also runs a high-volume news and explainer feed covering cryptography, security, chips, cloud and cryptocurrency.
Why I recommend it: Free, no paywall. Two halves, and they deserve different levels of trust. The 2017 SHA-1 collision material is genuine, checkable primary research and still the best way to see a broken hash function with your own eyes. The current news feed is a different thing: posts appear every few minutes, carry no named author, and the site also covers 'provably fair' crypto gambling, which sits close to affiliate territory. I have deliberately not wired it into the headlines here — use the archive, and confirm any breaking claim against a named outlet before you repeat it.