Cubism.js is a D3 plugin for visualizing time series. Use Cubism to construct better realtime dashboards, pulling data from Graphite, Cube and other sources.

Pretty impressive image filters for canvas, with a nice expressive API.

These look like some effective animation tools.

A 2d game engine written in Lua. Used to program Mari0 -- the Portal/Mario mashup.

See Mr Doob: https://twitter.com/#!/mrdoob/status/183324533808308225

A plain-text markup language for screenwriting. It mirrors the conventions that already exist. A markdown for screen writers.

ShareJS is an Operational Transform library for NodeJS & browsers by an ex-wave engineer.

A mustache-compatible template language library from the fine folks at Twitter.

A CSS-like query language for getting at properties in complex JSON objects. It feels just like CSS. What a great idea.

Gettext Style i18n for Modern JavaScript Apps

Another pushState url-based router. Recommended by sfoster. Relies on jQuery. Update: the author has made it Zepto-compatible after I dropped him a line. Awesome!

A hashChange router for the front end.

A mobile-focused Javascript framework with syntax inspired by jQuery.

Flow control libraries for handling asynchronous but ordered steps in Node JS.

Cron library for Node recommended by Mathias Bynens here http://stackoverflow.com/questions/5636051/cronjobs-in-node-js.

Cross-site request forgery protection for forms in EpxressJS apps. Yay!

A Node framework for accessing the Twitter API. May pair with Express for a simple Twitter search solution.

A pretty massive library for bringing Ruby-like class idioms to JavaScript. Interfaces, singletons, classes, multiple inheritance are all supported. It looks like he's using JavaScript's method lookups, rather than just copying every property. I think you may be able to just include the core.js module, making it ~3k when minified/gzipped.

Like SASS, but hotter, and written in Node. As whitespace-sensitive pre-compilers go, this one's syntax is ace (all the usual caveats of switching syntax apply).

Via David Slayden. To investigate.

How completely brilliant is this? A library for making any non-chainable API chain. It wraps the original function in a function that returns the result, or "this" if nothing comes back.

A WordPress transients interface with support for soft-expiration (use old content until new content is available), background updating of the transients (without having to wait for a cron job), and a chainable syntax that allows for one liners.

Sugar for Javascript objects. Fixes and patches implementations for spec'd features like indexOf forEach, etc. It also adds a few methods outside of spec. It extends native objects, but does it tastefully. Could be useful in the right context.

A Javascript library for currency formatting.

An MVC structure for Javascript. A bit like Backbone.js, but without the dependency on Underscore.js. This may be irrelevant depending on the project, though, since Underscore is so darn handy.

A Javascript library that does essentially what R does.

Nest provides a high-level, simple scenegraph for Processing, loosely following the API for the scenegraph and display list implemented by ActionScript 3.

A swiss army knife for converting markup languages to other markup languages:

- Textile to Markdown
- Markdown to Textile
- Textile to Latex
- Markdown to HTML
- Etc

It's a Haskell command-line tool, but he set up a web service demo, too.

A huge collection of "batteries included" classes for Processing or Java, including particle systems, color, audio, more.

"The Swiss Army Knife of Vector Graphics Scripting". Compatible with Scriptographer (Adobe scripting environment). It's a bit like Processing. Notable differences are:

- Not state-based, or pixel-based. Rather, vector-based.
- Includes a DOM.
- Has an intuitive layer system, ala Photoshop.
- Javascript!
- Everything is sandboxed using closures (more on that below).

One cool and interesting feature is that event functions are global and called implicitly (e.g. just define function onFrame (){}). However, these calls are only global within the scope of the PaperScript, so everything is sandboxed. I anticipate this would be easier for beginners than an event subscribe model.

An intro tutorial to three.js.

A javascript library for Bayesian learning.

An open-source Actionscript game library.

A basic Javascript animation library with a Flash-like GUI for editing animations.

Dustin Diaz bundles together a bunch of agnostic Javascript modules to make a microframework. Classical inheritance through Klass, utilities through Underscore, a selector engine, lots more.

A canvas abstraction layer as objects. Cool.

Opensource library for generating ePub format books.

A tiny **643-byte** non-blocking script loader and dependency manager. Just the
basics.

Exact and full port of the Django template language for PHP.

A PHP template language inspired by Django.

A video projection mapping library for Processing (allowing you to map textures to a real-world object).

Physics-based fluid dynamics library for Processing.

A library that handles mass, velocity, particles. No collision.

A brilliant dependency and loading manager for Javascript. Basic setup will non-blocking load JS files over HTTP. Optionally, a bundled Rhino bash script can compile JS into a single file using Google Closure Compiler (CSS, too while your're at it).

A javascript to easily add cross-browser asynchronous external JS files.

A microformats parser for Ruby.

Ultra-basic, no-cruft modal box script. All CSS is in-lined programatically. Looks like a better choice than ThickBox.

A javascript port of the Processing animation language. Renders in <canvas>. Nice!

Feature testing javascript suite for HTML 5 elements. It also "registers" html 5 elements in IE, so you can use them with abandon.

The php5 script that strips and gzips a collection of CSS and JS files, speeding up HTTP requests enormously.

A javascript library being developed by folks at Apple. Reputedly pushing the boundaries of complex javascriptery.

Add a javascript rendered "wet floor effect" to images by simply adding a class name.

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