I thought this was just... plain... awesome. I just learned about this today and I wanted to pass this very unique news along to everyone.
Long story short, Valve is releasing a fully, dev supported movie creation platform that allows people to make their own "game" movies (think machinima) using the same game engines from their games.
Honestly, my explanation although brief can't do this new Valve project justice. Ok, enough from me, check it out for yourselves! Should be especially intriguing for all you budding machinima film makers.