Okay, I won't lie...It doesn't seem like the deepest or most complex, or historically accurate picture in the world, but it does look like a fun guilty pleasure and I also enjoy movies that just take you on a ride.
In this N.Y. Times "Anatomy of a Scene" video clip director, Roland Emmerich, breaks down some of the Special FX considerations for his new prehistoric epic action movie 10,000 B.C. It's quite amazing to marvel at how far special FX of things like fur and water have come and well they can be blended in to live action movies.
While complicated special FX like those in this scene are probably beyond the equipment and skill level of most Down and Dirty filmmakers, there are a growing number of tools and tutorials out there that can help low-budget action directors digitally accomplish otherwise impossible filmmaking feats.
(Note: The video on the left tab is the scene and the video on the right tab is the director commentary.)