I gave a presentation on Parrot at Penguicon today.
The title was "Parrot Compiler Toolkit: building dynamics languages with Parrot" or some such.
Slides are probably here, but they only cover the first half of the talk. The second half of the talk was walking through the implementation of GIL, the Generic Imperative Language that I threw together in a coffee shop in Phoenix a month ago.
The makefile in that repository won't actually work for anyone who doesn't keep their parrot tree at/home/tene/src/parrot.svn. I'm too lazy to fix it. You can regenerate it yourself with the instructions in the readme.
I forgot to actually mention Parrot's website, the mailing list, or the irc channel, #parrot on irc.perl.org. I also forgot to mention KJ's PCT tutorial which is a MUCH more in-depth reference for implementing a compiler on Parrot.
It was fun, and I got a very nice response. I hope some of the people there come take a look and start contributing. If anyone that attended reads this, please leave a comment here.