Source Wireframe Kit - Library of 537 blocks for desktop and mobile prototyping
Lax.js - Create beautiful & smooth animations when you scroll
Platforma - Wireframe library of layouts and UI elements
WOW.js - Animate elements on-scroll to catch attention. Such Magic.
iOS Wireframing UX Kit - An easy, speedy way to wireframe for iOS
ScrollMagic - The jQuery plugin for magical scroll interactions.