The is a new offical Plugin from Ryan Geiss:

Monkey v1.0


What is Monkey?

Monkey is a 3D-accelerated Winamp visualization plug-in that takes you on a fascinating journey through a never-ending network of caves, tunnels, and passageways. Monkey-Homepage


Monkey v1.0


Also Geiss II is in development and a preview version of it is available:
Geiss II Preview

Put in the the winamp plugins dir.

According to a post in the winamp forum the frame rates are very low at the moment:
Forum Post