AS3 particle-generator with Flex

Been playing around a bit with the new Adobe software Flex and I like it a lot. I have not used it that much yet but I realize that the possibilities are enormous. For a coder like me, it's a great relief to be able to use ActionScript 3.0 directly in Flex. Without the timeline and graphic interface that is such a prominent part of the normal Flash software.
Michael Battle is a flash developer who recently started to play around with AS3. He shared the source code of a particle generator and I had a go with it in Flex. I have only changed the parameters a bit and used other colors. As you can see from his experiments there are a great improvement in performance in AS3 compared to earlier versions.
Instructions
Click and drag on the green area (flash 9 requred)