This script makes reading Stephen Wolfram's "New Kind of Science" (wolframscience.com/nks) a little more tolerable by:

• prefetching adjacent pages to the one you're currently reading
• adding keyboard navigation w. left/right arrow keys

To use it,

• copy-paste it into the dev console at wolframscience.com/nks, OR
• add it to a browser extension that manages user-scripts, like Tampermonkey for chrome