stencil , feedback and accumulation buffer

I want to know how the stencil, the feedback and the accumulation buffers work, and what they can be used for.
I guess I can make motion blurs with the feedback buffer, and make shadows and reflections with the stencil buffer, but what can I do with the accumulation buffer?
And I would like to know what brute force is

[This message has been edited by poca (edited 08-12-2003).]

Search for the RedBook.pdf on the web!

The feedback buffer is used to report back what primitives would have been drawn where. It doesn’t draw anything.
The accumulation buffer is used to do blur, depth of field, antialiasing effects, image filters etc. by drawing a scene multiple times at with different views.
The stencil buffer is basically a very flexible per pixel mask.

Brute Force is a nice action game for the Xbox taking it literally.

Using a brute force algorithm normally means to calculate everything without doing clever optimizations.