From Mathias Horrigan:

“The power of Stage3D, works for both 2D and 3D! New features such as mouse lock, right click, and middle click events. The Starling framework is recommended for 2D games. The new flash will also have sprite sheet tool built in allowing you to export as any extension! Also a particle designer. Gives us a great idea where flash is going.” 

Particle Video with Flash Player Stage3D

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Bonus link: [ Particle Video - explanation ]

From Clockmaker labs:

“I create particle demo with Starling Framework. The wave graphics is made by Frocessing in Spark project, the particle graphics is made by Starling Framework.”

Hey, full sources included!

Little music visualiser made using Away3D 4 and Flint Particles.
Double-click to go full-screen.

Flint particles system. Now with Away3d, Flare3d and Alternativa3d support (Stage3D).