Elevator.js
Finally, a "back to top" button that behaves like a real elevator.
Hoppscotch
👽 Open source API development ecosystem https://hoppscotch.io
Scroll Trigger
Triggers classes on html elements based on the scroll position. Uses requestAnimationFrame so it doesn't jack the users scroll.
Popmotion
A 12kb Javascript motion engine. Use for animation, physics and input tracking.
Barba.js
Create badass, fluid and smooth transition between your website's pages.
Dynamics.js
Javascript library to create physics-based CSS animations
Bounce.js
Create beautiful CSS3 powered animations in no time.
Snabbt.js
Fast animations with javascript and CSS transforms
Move.js
CSS3 backed JavaScript animation framework
Granim.js
Create fluid and interactive gradients animations with this small (< 10 kB) js library.
jQuery.terminal
jQuery Terminal Emulator - JavaScript library for creating web-based terminals with custom commands