Lightspark is a free, opensource SWF (Flash) player. It supports OpenGL-based rendering and LLVM-based ActionScript execution. It supports most of ActionScript 3.0 and has a Mozilla-compatible plug-in. It uses OpenGL shaders (GLSL). It is free software released under the terms of the GNU LGPL version 3. Lightspark is compatible with H.264 Flash videos on YouTube.
Website: http://lightspark.sourceforge.net/ License: LGPLv3