Jquery Waypoints
Waypoints is a small jQuery plugin that makes it easy to execute a function whenever you scroll to an element.
Bind.js
bind.js - simple two way data binding to HTML and callbacks
Persist State
jQuery Ui widget that will transparently save the state of checkboxes, inputs, selects, etc in localStorage, restoring these on the user's next visit to the page.
Fragment.js
A tiny tool for easily loading html fragments and templates
Eqcss
EQCSS is a plugin that introduces Element Queries, Scoped CSS, a Parent selector, and responsive JavaScript to all browsers IE8 and up
Porthole
A proxy to safely communicate to cross-domain iframes in javascript
jQuery.lazy
A lightweight, fast, feature-rich, powerful and highly configurable delayed content, image and background lazy loading plugin for jQuery & Zepto.
Double
jQuery plugin for hiring doubles
Scrob Master
Master your scroll events.
jScrollPane
Pretty, customisable, cross browser replacement scrollbars
Egjs Infinitegrid
A module used to arrange card elements including content infinitely on a grid layout.
Veinjs
Injects CSS into the document (it's a perfectly legal procedure)
Viewport
Gets the dimensions of the Viewport and beyond.
Html
A simple, extensible way to work directly with the DOM.
Masonry
Layout elements in a grid, like a mason fitting stones in a wall
Hapi
The Simple, Secure Framework Developers Trust
Tether
A positioning engine to make overlays, tooltips and dropdowns better #hubspot-open-source