I had a great idea... can you incorporate Havok Physics simulator into a flash game or something to make cool physics (like ragdoll effects)? Just wonderin...
I don't think actually using Havok would work for a few reasons. It's geared toward commercial game developers, so the licensing fees are almost certainly quite high. It's presumably written in C, which means you'd need to use the experimental Alchemy compiler to get it to work in Flash. It's designed for 3D stuff, which Flash really can't do too well, yet.