Collapse is a jQuery plugin for creating progressive disclosure designs.

Basically, Collapse provides a nice, lightweight (600b) solution for expanding and collapsing website content.

What’s the best about progressive disclosure interfaces is that they don’t confuse the users with any information they don’t need at hand.

The additional elements can be shown with a transition, e.g., a sliding motion.

Collapse features a number of options and callbacks (cookie support is notable) thus it’s suitable for creating even the fanciest of web apps.

• Website: http://webcloud.se/code/jQuery-Collapse/

Etherpad is an open source web service that allows multi-user collaboration on a single document.

Etherpad is hosted on a number of public sites used daily for private (piratepad) and public document sharing.

The service offers a full-geared GUI for document editing, viewing their history, and sharing them.

Etherpad is particularly advantageous for cryptic people, as it’s a safe, non-Google way of sharing documents.

• Website: http://etherpad.org/

InAppSettingsKit is a iOS framework for easily adding in-application settings to your apps.

The framework is released under the BSD license, and is completely open-source.

With InAppSettingsKit, you can add several useful features to your applications within minutes:

• On/off switches for settings;
• Mail sending from within your app;
• URL opener;
• Footers;
• A custom view controller;
• etc.

• Website: http://www.inappsettingskit.com/

Firmin is a JS animation library that uses CSS transforms and transitions.

Firmin has a minuscule API that works fine for creating neat, hardware-accelerated animations.

What’s interesting is that Firmin uses “relative” transforms for consecutive animations.

The library’s main drawback is the scarce support (WebKit only).

However, Firmin delivers in functionality and being easy to comprehend, so the library can definitely become a top pick for developing mobile, etc., applications.

• Website: http://extralogical.net/projects/firmin/

print.css is a library that strips unnecessary CSS from pages you want to print.

print.css removes practically everything except written text and styling that’s necessary for it to be properly aligned.

Paper costs money, and you can help both the ecosytem and your visitor’s in a single shot.

And seriously, at least print.css is much more straight to the point than other eco-friendly libraries, and also less annoying than the ‘please do not print this email unless it is absolutely necessary’ email signatures.

• Website: http://printstylesheet.com/

Satchless is an e-commerce framework built on top of Python and Django.

Satchless is built upon the very idea that there is no “one size fits all”, and that “a good framework should give you just the right tools to prototype, test and build an efficient solution that suits you and your business.”

The coding is module-based, and the documentation helps you set up the first modules (cart, catalog, etc.).

• Website: http://satchless.com/