It's not obscure, but, for me, Wikipedia is the ultimate example of the old internet that still persists today.
Free to use, no account required, ad free, non-corporate, multilingual, heavily biased toward text, simple and utilitarian design. Hyperlinks concatenate relevant pieces of information, which serve as the means to navigate the site. The code is very simple (seriously, view the page source of a wikipiedia article). It's based on the human desire to learn and share knowledge with others, and has remained resilient to corruption by commercial interests that pervert that desire for monetary gain. It's a beautiful thing.