It seems that this year the Saxxy awards SourceFilmMaker competition will be open to other games than just TF2, and due to that, VALVe has released the "Portal Content Pack DLC" including all models, particles and sounds for the SFM, for those who still don't have them. The only con is that no Portal-specific effects like light bridges, gels, or portals are included >.<

Nice chance to start up learning SFM anyways, isn't it?

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hehe... wondering if someone could take shots in-game that use portals, and then cut to Filmmaker rendered parts where the portals are just so conveniently offscreen

You could import the particle effects and models for the portals, then conveniently never let the camera look into one.