If you use Gmail and you'd like a simplified interface that doesn't use AJAX, loads fast and works well in most browsers, try the basic HTML view. Gmail links to this version at the bottom of the page, but you can also access it if you go to http://mail.google.com/mail/h/.
Until recently, Gmail didn't have the option to set the basic HTML version as the default interface and you had to bookmark its URL or click on the link from Gmail's footer. Now there's an option to always go to the HTML version, every time you load Gmail.
Please keep in mind that the simplified version lacks many useful features: * integration with Google Docs and Google Calendar * keyboard shortcuts * integrated chat * composing options: spell checker, rich formatting, address auto-complete, custom From address * ads (useful feature?), related pages, tracking packages and addresses * contact management * web clips.
Google recommends to use the basic HTML view for slow Internet connections, although you may find it useful when you use exotic browsers or when the standard version doesn't work. If you change your mind and you want to go back to the AJAX version, click on "Standard View". Apparently, the standard view loads much faster thanks to some aggressive optimization.