In my recent project, http://www.myflashlab.com/2010/01/27/contactform-class/ I was trying to do a lot of data transfer to and from flash to PHP (or any serverside script), I had to send attachments to php, I even had to encrypt the data before the transfer and that stuff. having to do all these things, I decided to write a class to take care of all these things for me.
so I wrote this fine class that I have named it FileSaver! 
This class is good for the following purposes:
- you want to save a file from your flash app to your desktop.
- you want to save a file from your flash app to your server.
- you want to save a file to your server and send some variables along with it.
- you want to send some variables to a server side script.
- you can encrypt the data before sending them out to server script.
The ContactForm class will help you create complex web forms easily. you can create unlimited number of fields and positioning them horizontally or vertically and manually. all colors are set dynamically and the whole class has been built through pure coding.