Cached Commons is a repository of many JavaScript libraries that are cached, optimized and hosted on Github's CDN.

It is free for everyone and works by simply using the URLs mentioned (original or the minimized versions) as the script tag URLs.

Compared to the popular Google Libraries API, it hosts a much more number of libraries including many jQuery plugins, visualization or the ones for markup.

The only downside for now is that, there is only jQuery as a JS framework and hopefully, it'll start hosting others soon.

WebMatrix is a free kit by Microsoft which includes everything you need for creating websites on Windows.

The application itself enables you to control almost everything from a single interface like the code and database editor, web site and server management, search optimization, FTP publishing, and more.

The kit comes with:

• IIS Developer Express (a development Web server)
• ASP.NET (a Web framework)
• SQL Server Compact (an embedded database)

and with just a click, you can install open source applications like WordPress, Drupal, DotNetNuke, etc.

WebMatrix has also some nice features like the ability to run a SEO report or monitor real-time Web requests and responses to track down problems right at the source.

OneWay is a tiny, free and open source Mac OS X application for instantly uploading any file/folder.

It can upload data to FTP, SFTP or Amazon S3 directly from your Finder.

You can save the frequently used upload locations to the context menu (project-backups, personal-backups, etc) and send the files with a ctrl+click.

OneWay is very functional for web designers/developers while live-testing a web project as it usually requires frequent updates or easily backing up project files.

Show Slow is an open source tool (and, optionally, a free web-based service) for monitoring website performance metrics over time.

It simply collects the results from YSlow and Page Speed rankings and graphs them to show you how various changes to the website can affect the performance.

And, it can do this regularly to help you see the improvements done within time.

Bowline is an open source framework (not a platform like Adobe AIR or Titanium) for creating desktop applications with Ruby, HTML and JavaScript.

It respects MVC, views can be designed in HTML5/CSS3 and then you can bind them to your Ruby models.

There's no request/response cycle. Any changes in models automatically get reflected in the view.

Applications built with Bowline currently works in Mac OS X + Linux and Windows support is on the way.

BrowserLab, a web-based service by Adobe, enables you to test websites on multiple browsers and OSs.

It is possible to create a custom browser set where the screenshots will be created only for those browsers (also helps speeding up the results).

Screenshots can be previewed in 2-up or onion-skin views which makes comparing multiple versions easier and x/y rulers can be used for sensitive measurements..

The service currently supports different Firefox, Safari and IE versions for Windows and Mac OS X. However, it is still in beta and new browsers are added within time.

BrowserLab is part of the Adobe CS Live and free for 1 year if you sign-up before April 30, 2011.

SiteFusion is an open source and server-based development platform where a XUL client runs code written with PHP.

The application runs on a server generating JavaScript commands but looks and behaves like native desktop applications.

The output is platform-independent and can access the client filesystem, run programs, play sounds ,etc.

There are no extra configurations required than running a website as the XUL client connects to a regular web server.

And, it offers a two-way real-time ZLib compressed communication which is great for building real-time applications.

ProtoFluid is a free web-based tool which eases web application testing on various screen sizes and orientations.

It simply asks you you to mention the website to be tested and the desired screen size (sizes for popular devices are predefined).

Once launched, you can see the website inside a modal box with the mentioned size, and with a click, you can change the orientation.

For anyone, who prefers to complete this task on the browser-side, web developer add-on has the resize function, but keep in mind that you can still use Firebug or other tools at the fullscreen view with such a web-based app.

Also, it lets you design for CSS3 compliant (mobile) browsers using Media Queries.

@anywhere is a set new JavaScript-based methods by Twitter which helps integrating websites with the service easier and better.

It simply works by registering to the @anywhere platform and inserting few lines of JavaScript.

The integration methods are:

• Auto-linkification of @usernames
• Hovercards
• Follow buttons
• Tweet Box (enabling users to tweet from your website)
• User login & signup

It is possible to let the script search for the Twitter usernames in a whole web page or, better, define specific elements/IDs/classes to make it work faster.

PixelZoomer is a very handy Firefox extension for web developers which can replace the step of taking screenshots of a web page and pasting it into an image editing software for making pixel-perfect measurements.

Once it is activated (clicking an icon at the bottom of Firefox), a custom window with the web page screenshot is loaded.

Inside this window, you can zoom in/out, select specific areas to see their width/height and pick the color of a pixel.

The extension has an option to grab the screenshots using Java runtime (more accurate) or Canvas (faster).