Base2 is exactly what the title says,  Unlike the major libraries that strive to enhance javascript with shiny new features, Base2 strives to achieve a clean, browser independent execution environment.  In many ways base2 does for javascript what Blueprint, Tripoli et al. do for CSS.

Key Features:

• Inconsistent enumeration across platforms
• instanceof doesn’t always work
• typeof is inconsistent (RegExps identify as type “function” in Mozilla browsers)
• Consistent object/platform detection
• Other various bugs

And the sugar:

• A mechanism for inheritance
• A decent hash object
• Array and String generics
• Array extras
• Support for ISO date parsing

Playing with the library, it really is a breath of fresh air in many respects.  It’s lightweight (20kb compessed & 6kb) gziped and loaded with features that make day to day javascript development faster and easier.  Most importantly, it raises the bar for all browsers by providing Javascript 1.6 features to browsers other than Firefox.

You can get it online at

http://code.google.com/p/base2/ 

and there’s an excellent introduction at

http://dean.edwards.name/weblog/2007/12/base2-intro/ 

What is it:

FastInit is a small JS file to create a Faster window.onload. It implements a powerful onload function queue that fires once teh dom is ready and before all images have been downloaded. Ideally, this results in a dramatic decrease in a pages initialization time.

How it Works

You any functions to the queue by using the FastInit.addOnLoad( function 1, function 2, …); function. All functions are fired in the order in which they were added to the queue. addOnLoad can be called as many times as is necessary. It fails gracefully to standard handlers if the browser doesn’t support the faster methods.

Requirements

As of version 1.4.1 the need for Prototype has been removed freeing the code for use in any project where a speedy onload method is needed.

Check it out here:

http://tetlaw.id.au/view/javascript/fastinit

An effort is underway to merge several well known Prototype based widgets into a single widget library built on top of the prototype / scriptaculous stack.  It’s already in a usable form combining the following widgets into a single js file.

• Dock
• Carousel
• Shadow
• Window

You can find it online at http://www.prototype-ui.com/