SoundManager is a Javascript Sound API which effectively maps most of the native sound capabilities of Flash 8 to Javascript.
It enables you to control sound in a cross-browser/platform environment, using a language you already know.

A sample SoundManager code would be:
soundManager.createSound('myNewSound','/path/to/some.mp3');
soundManager.play('myNewSound');
soundManager.setVolume(’myNewSound’,50);
You see that it is really easy. This JavaScript Flash Sound API has other powerful controls like:
- stream
- autoplay
- onid3 - for ID3 tag displaying
- whileplaying
- and more..
Using SoundManager, you can easily create sound based web applications or more interactive background sounds for non-Flash websites.
Requirements: Flash plugin 8+
Compatibility: All Major Browsers
JW FLV Media Player is a complete solution for adding video and audio to your website.
Some features:
- supports playback of any format the Adobe Flash Player can handle (FLV, but also MP3, H264, SWF, JPG, PNG and GIF).
- supports RTMP and HTTP (Lighttpd) streaming, RSS, XSPF and ASX playlists.
- has a JavaScript API.
- accessibility features.

This FLV player has so many other features like Youtube support or Google Analytics support for tracking the statistics.
JW FLV Media Player also provides an online setup wizard which can be used to create a ready-to-use configuration file.
The application is free for personal use and licences needed for commercial uses.
Requirements: No Requirements
Compatibility: All Major Browsers
Gaia is a front-end Flash framework for AS2 and AS3 and is designed to dramatically reduce development time.
It provides solutions to the challenges and repeated tasks faced with front-end Flash site development, such as navigation, transitions, preloading, asset management, site structure and deep linking.

There is a nice screencast here.
Gaia’s unique event hijacking engine enables you to achieve some really complex behavior with very little code. Additionally, Gaia has scaffolding which generates all the base files for your site, including Flash files, class files, and even exclude.xml files!
It uses SWFObject and SWFAddress and also forces applications to support deep linking (great for SEO purposes).
If you’re developing Flash sites and want to speed up your Flash workflow with rapid development and don’t want to have to learn a complicated framework API, give Gaia a test drive.
Compatibility: AS2 & AS3
Flash toolkit PowerCursor, an amazing idea, helps creating interfaces with the touch feeling. Users can experience touch feelings like roughness, volume, pressure, stickiness or mass in a graphical interface.
The software engine consists of a set of force field objects that can be added to any Flash project: holes, hills, slopes, roughs, walls, whirls, and more.

How it works?
PowerCursor uses a technique called ‘optically simulated haptic feedback’ to evoke the tactile experience. It simply, using active cursor displacements, guides the user towards preferred positions or communicate properties of the interface to the user. Due to these cursor displacements a hole becomes an easily accessible part of the screen, whereas a bump area is hard to access.
Who can use PowerCursor?
Although skilled programmers might dive deeper into the toolkit’s API to control the PowerCursor objects on a code level, the toolkit can be used by non-programmers with basic Flash skills.
XML Flash galleries are very easy to use & update. When there is a flickr support too, than it is great as it will be totally automated.
Polaroid Gallery is a free flash gallery with splash effect that can get the image data from an XML file or a flickr account.

Pictures is automatically scaled, centered and smoothed when they are loaded. Splash loading effect is totally random, this makes the look of the gallery different every time it is loaded. Images can be dragged & dropped anywhere in the gallery.
Besides the image gallery SWF file, FLA source can be downloaded too.
Macromedia Flash & ajax, by default, has lacking seo features as there is, normally, only 1 url address for all the contents within these web applications.
A seo & deep linking solution for flash and ajax is SWFAddress that is developed by Asual.

SWFAddress is a small, but powerful library that provides deep linking for Flash and Ajax. It’s a developer tool, allowing creation of unique virtual URLs that can point to a website section or an application state. SWFAddress enables a number of important capabilities which are missing in today’s rich web technologies including:
- Bookmarking in a browser or social website
- Sending links via email or instant messenger
- Finding specific content with the major search engines
- Utilizing browser history and reload buttons
Seo & deep linking for Silverlight is on the way. There is already an example for Silverlight.
Tip: Php Developers, there is a specific php version of XML/SWF Charts here.
XML/SWF Charts is a very nice tool for creating attractive charts. Creating bar charts, pie charts, line charts & more is posible with XML/SWF Charts.
Using XML/SWF Charts is free (some limitations).
How To Use?
Create an XML source to describe a chart, then pass it to this tool’s flash file to generate the chart. The XML source can be prepared manually, or generated dynamically using any scripting language (PHP, ASP, CFML, Perl, etc.)

Features:
- Web charts and graphs from dynamic data
- Live and interactive chart updates without reloading the web page
- Clickable charts, and drill-down
- Animated transitions
- Printable charts
- Simple and flexible chart generation
- Quality Flash graphics
- Supports unicode text to display special characters and any language

Chart types:
- Line charts
- Column charts
- Stacked column charts
- Floating column charts
- 3D column charts
- Stacked 3D column charts
- Parallel 3D column charts
- Pie charts
- 3D Pie charts
- Bar charts
- Stacked bar charts
- Floating bar charts
- Area charts charts
- Stacked area charts
- Candlestick charts
- Scatter charts
- Polar charts
- Mixed charts
- Composite charts
- Joined charts
Requirements: Flash Player 6+