This week a need came up in a client project. The client's team wanted to be able to navigate to their tours (pages) in the admin page-list by different criteria (operator, brand, boat, etc.). You can do this in Lister already (filtering by page references), but the client was looking for some predefined navigation paths in the main page list, as they thought this would be a helpful and time saving optimization, as they spend a lot of time in ProcessWire. They don't always know the exact tour at first, so starting from an operator, brand or boat helps them get to where they want to go more quickly. Once implemented, I thought it was actually quite useful for a lot of situations so decided to develop it into a module on my own time, and that's now available for download in the modules directory. I've published a new blog post that describes it more and covers all the details—
https://processwire.com/blog/posts/page-list-custom-children-module/