Lately I've been reading up on alot of AI systems and how to implement them in games, so here's the second project I've decided to work into a useful add-on for DarkGDK. It's basically a c++ versions of the algorithms presented here:
http://www.red3d.com/cwr/steer/
As of now I only have the avoidance and standard seek/flee target behaviors completed, but I plan on organizing it so that you can create herds and flocks, or issue paths for an agent to follow. It would go well with my pathfinding algorithm but it's currently setup so that they wouldn't work together so I might fix that sooner or later.
Just to note, it is designed for animals/creatures/people. The agents move backwards or strafe at times depending on the behavior, so it wouldn't work with vehicles which have specifiable turn radii.
Features and Progress:

= done with no extensive testing or nearly complete

= in progress

= haven't begun

= phased out

smoothed directional changes

darkGDK linked objects

seek / flee behavior

nothing + stand ground behavior

collision avoidance

specifiable agent mass, maxForce and maxSpeed

following / avoiding behavior

flock behavior

herd behavior

path following

kinematic collisions
Note: Unfortunately I can't upload videos so there isn't much to actually show except some screenshots of behaviors being carried out.
Screenshots

Two agents avoiding a predicted collision with each other

Simple implementation using agents linked to native darkGDK objects