Ola is a smooth animation library for inbetweening / interpolating numbers in realtime.
barba.js is a small, flexible and dependency free library that helps you creating fluid and smooth transitions between your website's pages.
Woco Accordion is a simple, user-friendly and lightweight jQuery accordion plugin with smooth animations powered by CSS3 transitions.
iSlider is a smooth slider for Mobile WebApp, HTML5 App, Hybrid App.
smoothState.js is a jQuery plugin that progressively enhances website page loads to behave more like a single-page application.
Jump To is a jQuery plugin that let you create a smooth jump to sub navigational menu in one JS call. The menu can be used to assist your navigation for pages with a lot of content.
Slickhover.js is a lightweight useful jQuery plugin that produces a slick and smooth hover effect that fades out images and shows a custom icon when a user hovers over an image.
rlsmooth is a jQuery plugin with smooth effect scroll animation. Its a small flowing plugin.
Smooth Div Scroll is a jQuery plugin that scrolls content horizontally left or right. Smooth Div Scroll does not limit the scrolling to distinct steps. There are no other buttons or links on outside the scroller since the scrolling is done using hotspots within the scrollable area, the mouse wheel or via autoscrolling. Unobtrusive and smooth is the key here.