Dear internet, please give up on April Fool's jokes. YouTube's is untoppable: A "text-only mode" that renders videos as colored ASCII art. Clever, gorgeous, perverse.
Just click the TEXTp resolution in the bottom right corner of a supported video, and it'll be shown as a pulsating, hypnotizing square of stylized digital pointilism. The results can be spectacular, like with Lego Matrix, which seems like it was born to be watched this way.