Chrome is Google's browser. I recommend running the beta version as it's very stable and most up to date.
Chrome actually uses WebKit, which is the same html/css rendering engine that Safari uses, but has a much faster javascript engine and completely different network stack. It's currently the fastest browser by far.
The best feature of Chrome is that each tab is running in it's own windows process. For the non-techies, that basically means that it can't talk to any other browser tab or window which makes any problems caused by that web page to only effect that web page. If a page causes a crash, only that browser tab crashes. The rest of chrome is alive and well.
As far as resource usage goes, it is a little more of a memory hog than Opera for the same pages open at the same time, but the benefit of single process tabs offsets that issue by a long mile.
As I think I've told you before, I use both Opera and Chrome (and Firefox and rarely IE and Safari). Chrome has become my default browser on both windows and mac. It's really become quite stable.
You can download it here:
http://www.google.com/chromeIf you want to use the beta version, make sure to click the beta link on that page instead of the download link.