A friend of mine on Twitter said that he remembers when the MIME format for email attachments was competing with the UUencode format for email attachments -- kind of like VHS versus Betamax. Here's the Wikipedia article on the format that lost.
This is a free website that allows users to search for books not only by the title or author, but by ISBN numbers.
I found this helpful for when textbooks are hard to find. Instructors usually provide the ISBN numbers in their syllabi and this is one resource a student could use to locate out-of-stock books.
Here's the CLI program I used to read email at the University of Virginia in 1992, when I first started using the Internet. Again, not the web. It didn't exist yet.