jQuery JSONP
jquery jsonp plugin
Onionskin
A client- and server-side multi-layer cache manager library
Easy Pie Chart
Lightweight jQuery plugin to render simple, animated and retina ready pie charts with the HTML5 canvas element
Store.js
localStorage wrapper for all browsers without using cookies or flash. Uses localStorage, globalStorage, and userData behavior under the hood
Rusha
High-performance pure-javascript SHA1 implementation suitable for large binary data, reaching up to half the native speed.
Papa Parse
Fast and powerful CSV (delimited text) parser that gracefully handles large files and malformed input
Mesh.js
common, streamable interface for synchronizing data
Holmes
Fast and easy searching inside a page
Backgrid
Finally, an easily stylable semantic HTML data grid widget with a Javascript API that doesn't suck.
Zangodb
MongoDB-like interface for HTML5 IndexedDB
String Score
JavaScript string ranking 0 for no match upto 1 for perfect... "String".score("str"); //=> 0.825
Lovefield
Lovefield is a relational database for web apps. Written in JavaScript, works cross-browser. Provides SQL-like APIs that are fast, safe, and easy to use.
Polychart2
Version 2 of Polychart.js
D3 Cloud
Create word clouds in JavaScript.
Alchemy
Alchemy.js is a graph drawing application built in d3.
Mindb
Database on JavaScript