store.js : localStorage wrapper for all browsers without using cookies or flash. Uses localStorage, globalStorage, and userData behavior under the hood.
DOMAssistant : The modular lightweight JavaScript library, with CSS selectors, event handling, AJAX and complete Unicode support
Bliss.js : Want to use Vanilla JS but find native APIs a bit unwieldy? Bliss is for you
Prototype : Easy Ajax and DOM manipulation for dynamic web applications
DOM Storage Query Language (DomSQL) is an SQL inspired interface for DOM Storage (or Web Storage as defined in the W3C working draft).