Neil McAllister has a story at PC World about "Chromium", the source code for Google's open source browser, "Chrome".

   http://www.pcworld.idg.com.au/index.php/id;1913014503

The size of the source kit is 2.4 GB.
He discusses what other projects' contributed code was used.
Google indicates their work on non-windows versions is just barely started.
Slashdot has some speculation on this.

   http://developers.slashdot.org/article.pl?sid=08/09/13/0328200

Chromium Source download:
http://code.google.com/chromium/

Javascript virtual machine used in Chrome/Chromium:
http://code.google.com/p/v8/