Came here to give Google Notebook my respects and not disappointed.
I miss Google Sets. Such a weird little feature. You could input “Donatello, Raphael, Michaelangelo” and it would tell you the missing elements: “Leonardo, Splinter, Shredder, Bebop, Rocksteady, Krang...”
Don’t forget Google News Archive. Google scanned millions of pages of newspapers, including nearly 130 years worth in my town (Spokane, WA). It was a fantastic source for local history especially because it was searchable. Then the search function began to degrade, and last fall it stopped working entirely. They digitized papers are still there but unless you know the date that something happened, they are difficult to use.