Improbable Research website** that an annotated collection of papers that aim to expose predatory journals has been published. This mainly consists of papers that are nonsense and were devised to show that predatory journals will accept anything. Each paper has a short introduction and links to news items etc. that reacted to the "sting".
Faulkes, Z. (2017). Stinging the Predators: A collection of papers that should never have been published. Figshare. DOI: https://doi.org/10.6084/m9.figshare.5248264
A useful collection if you are discussing this topic with students/researchers: my only caveat is that it does not state clearly that the permission of the copyright owners was sought.
**a long-standing website/magazine that takes a droll and sceptical perspective on scientific output and has presented the ig-noble prizes since 1991
Photo by Sheila Webber: Sheffield Botanic Gardens, August 2017