There's a pretty cool look at the first Y Combinator class at 48:56 - http://www.youtube.com/watch?v=0NRL7YsXjSg&t=48m56s

Is there a (legal) downloadable version of this somewhere?

Looks legal to me. It was done buy Boondoggle Films and it's posted to their YouTube channel and they are linking to it from their site here:

http://www.boondogglefilms.com/aardvarkd.php

(I'm not going to lie - I bought the DVD when it came out in 2005)

I meant one I could download and watch offline. My TV doesn't have Youtube support (except via the HDMI port + a laptop).