UAParser.js - The Essential Web Development Tool for User-Agent Detection. Detect Browsers, OS, Devices, Bots, Apps, AI Crawlers, and more. Run in Browser (client-side) or Node.js (server-side).
Fallr.js - Fancy, simple, yet elegant message / alert / prompt / dialog / popup / notification / modal box jQuery plugin
Explr.js jQuery plugin - Create a "Windows Explorer"-like Tree structure
Sticklr.js - Sticky side panel jQuery plugin