brainbugz is a set of nodes and commands that enable you to use behavioural animation techniques on particles.
Features:
- 13 different steering desires: head direction, wander, seek, moth-seek, arrival, pursuit, shadow, following of curve / surface, obstacle avoidance, alignment, cohesion, separation, keep distance
- all desired can be used as stand alone force fields
- desires can be combined with each other and / or standard fields to achieve complex higher level behaviours (e.g. flocking)
- easy to use interface, no scripting needed to setup a behavioural system
- extensive documentation incl. tutorial
- example scenes

Big thanks to David Kirchner (david@film3d.de) for providing windows x64 compilations for Maya 2008, 2009 and 2010 which are added in the current release 1.4.0 (please note the updated mel code, too)! There is also a new version for linux x64 2009 by redpawfx. Please note I didn't have the time to test them all!

You can find the source code on my website or directly via svn here:

http://code.google.com/p/brainbugz/

Thanks everyone for the continued support, please remember to give a small (or big) donation to "Doctors without Borders" if you like and use this software. See the website for more information, a quick look at the docs, example animations etc.:
http://kolve.blogspot.com/2004/03/brainbugz.html