I first saw Scrollback being used on Tomahawk's website. You can embed a live chatbox to your website using this nodejs app. Archives all your conversations. Admin panel allows you to moderate conversations and hide messages. Customize your Scrollback chat widget to match the branding of your website or blog. Integrate your IRC channel with your Scrollback room, which means you could include github notifications for your project as well.

I like how simple this autocomplete is, and small.

Responsive. Style with CSS & control with JS. Usage of SVG. Other modern charting libraries I have posted about are Chart.js and C3.

Parse, validate, manipulate, and display dates in javascript.

A swipeable cards interface. The swipe-left/swipe-right for yes/no input. As seen in apps like Jelly and Tinder, and many others.

Great example of how you can use bounce.js to build animated (off-canvas) menus.

C3 makes it easy to generate D3-based charts by wrapping the code required to construct the entire chart. Responsive design. Includes most basic chart types; bar, pie, timeseries, scatter, etc

Passport is authentication middleware for Node.js. Extremely flexible and modular, Passport can be unobtrusively dropped in to any Express-based web application. A comprehensive set of strategies support authentication using a username and password, Facebook, Twitter, and more.

Basic front end web pages to bootstrap the creation of your website. Built on Express. Includes an auth system (using Passport) with login (including Facebook, Twitter, Google) and forgot password/reset password, and an admin area with user and group permissions. Utilizes lots of great packages such as Bootstrap, Grunt, Jade, Backbone.js, Bower, Mongoose, Underscore.js, and Font-Awesome.

There is a huge plethora of js charting libraries out there. I had used flot.js for Engadget's price graph, but it took some hackery to get it to work the way we wanted it to. This is a fairly newer one, that focuses on 6 of the most common charts and simplicity of use. There isn't currently any tooltips, but there is a pull request which does have them (and other features). There hadn't been much development on the repo for a while but the creator tweeted a WIP of responsive graphs with tooltips.

Tables - they've got a bad wrap in web dev history, but it's appropriate for tabular data. Here's some neat plugins for making your tables more useful in responsive design.

Laravel has some pretty sweet helper functions for generating urls/links and its auto-json-magic makes it building APIs super easy. This package allows us to port our routes over to JavaScript, and gives us a bunch of very familiar helper functions to use.

Open sourced by Salesforce. Written in javascript (coffeescript), with focus on building an API to events and easy of adding custom behavior (in comparison to say CKEditor). Has multi-user editing support (multi-cursor).

A great framework for starting an nodejs project, includes Express, MVC structure, bootstrap, native auth or oAuth login (via Twitter, Facebook, Google, etc), user account management, email support, and a couple basic themes to pick from.

Scribe is a lightweight wrapper for contentEditable, a library that only patches browser inconsistencies in contentEditable and, on top of that, ensured semantic markup. You can read why the Guardian built it here: http://www.theguardian.com/info/developer-blog/2014/mar/20/inside-the-guardians-cms-meet-scribe-an-extensible-rich-text-editor

node-webkit is an app runtime based on Chromium and node.js. You can write native apps in HTML and Javascript. It's created and open sourced by Intel. It makes it easy to package and distribute apps for Linux, Mac OSX and Windows. Popular projects built on node-webkit include LightBox and Popcorn Time.

Neat site that shows side by side how to do something in jquery and how to do it in native javascript. It's not saying don't use jquery, but your just doing something simple, in modern browsers, maybe you don't need the whole jquery library.

At only 3kb when gzipped, it is a lightweight and efficient library. Hammer doesn't require jQuery or other libraries to work. A jQuery plugin is available though. Hammer supports Tap, DoubleTap, Swipe, Drag, Pinch, and Rotate gestures.

Replicating and improving the lightbox module seen on Medium with fluid transitions.

A jQuery plugin for extracting dominant colors from images and applying it to its parent.