Google has announced plans to support native Mac and Linux versions of Chromium, but they have yet to be released. The folks at CodeWeavers have successfully built a version of Chromium, Google Chrome's codebase, for non-PowerPC Intel Macs. they named it CrossOver Chromium.
The description of CrossOver Chromium from Codeweavers.com:
CrossOver Chromium is a Mac and Linux port of the open source Chromium web browser. CrossOver Chromium is available for download from CodeWeavers, free of charge.

