Installing the Flex SDK
If you haven't downloaded the Flex SDK yet, go to the adobe website. Installing it is just a matter of extracting the zip file to your preferred directory(mine is in C:\flexSDK\bin). If you want to be able to compile from the command line, right click my computer, click on the Advance tab, then Environment Variables. Create a new system variable and put FLEX_HOME as the variable name, the location of your SDK(e.g. C:\Applications\flexSDK) as the value. Click ok. Look for the "Path" variable and click edit. At the end of the path variable value, put the following w/out the quotation marks, ";%FLEX_HOME%". Click ok until all windows are closed. You should be ready to go now. Go to your command line and type "mxmlc", if you see something like:
Adobe Flex Compiler (mxmlc)
Version 3.0.0 build 477
Copyright (c) 2004-2007 Adobe Systems, Inc. All rights reserved.
mxmlc [options] [defaultVar]
Use 'mxmlc -help' for more information.
It means you did it right.
Installing the Spket IDE, eclipse plugin
Note: Spket IDE flex editor is still in its early stage.
I was browsing for an alternative flex code editor(i.e. aside from Flex Builder) and I found spket IDE which is currently on version 1.6.12. I only needed to download the Eclipse plugin since I already have Eclipse(3.4.0) installed on my machine. I first made sure that I'm currently not running Eclipse, thenI extracted the zip file. Now, there should be a plugin and features folders. Browse inside those two directories and copy-paste the contents into your eclipse folder's features and plugin directories respectively.
Once done, open Eclipse and go to window->preferences and a new window will open. Collapse sa Spket tree, click on Flex SDK and specify your Flex SDK directory. Mine is in C:\flexSDK\. Change to the spket perspective as shown in the image below.

In an empty workspace, create a new project, under general, just select "Project". Name the project anything you want, I named mine "FlexTest". Create a new file, name it test.mxml (or whatever you like, as long as it ends with mxml). From here on, it's up to you to play with it. :)
Some notable pros and cons for this release:
Pros:
1. Very powerful code-completion feature
2. Drag and drop feature(look for the snippets window)
3. Free for non-commercial use
Cons:
1. No Flex compiler as of now
2. No visual designer
3. No Flex project support
4. No Flex file template available
Right now, the cons still a little outweigh the pros. All-in-all, it's still just an editor and you probably have to compile from the commandline. I'm looking forward to seeing improvements with this product.
Until next time 