I just saw something odd, I’m using Google Chrome browser and I right clicked a tab with GMAIL open and selected to view the source. All I had returned was :
<!DOCTYPE html><html><head></head><body><div></div></body></html>
How would they have managed to do this ? I didn’t think was possible ??
Because gmail is built with javascript it will also build the page dynamically after it is loaded with javascript.
gmail also uses a lot of iframes, you can have a look at the conent of those by inspecting them with Firebug for Firefox