Hi there,
I've added a demo of some of the stuff in yt to the svn repository in
trunk/doc/demo.html . I'm also going to keep a copy online at:
http://www.slac.stanford.edu/~mturk/yt_demo.html
(It covers a bunch, but not all, of the functionality in plotting and
data manipulation. I'll be adding other files about how to project in
parallel. Right now, for a non-derived field, it takes 3 minutes to
project the entire light cone simulation on 16 processors.)
-Matt