I just finished uploading a new tutorial to gotoAndLearn() which shows you the basics of using binary sockets in ActionScript 3. In the example I connect to POP3 mail server and use raw commands to retrieve messages. These techniques can be used to connect to a whole range of different servers such as FTP, IMAP, Telnet, etc. Socket programming can get extremely complex but the basics are nothing that any interactive designer can’t handle easily. Here is the POP3 command reference that I used in the tutorial.
Enjoy the tutorial!