Trick Gmail into thinking you're on an iPad for two-pane goodness | Web Crawler - CNET News: "Safari
This works on both the Mac and PC platforms. Just head into Safari's 'preferences' menu, then hop over to the 'advanced' tab. Go all the way to the bottom, and make sure the 'show develop in menu bar' box is checked. Close the menu, then you'll find a new 'develop' option in the main menu. On the Mac this can be found as one of the options on the top of the screen. On the PC, it's on the page-looking icon next to the Safari settings button on the top right of the screen.
In either case, find the develop menu, then go to user agent, then pick 'other.' You will get a menu to type a custom user agent string. Just drop this (found at blog Digital Inspiration) in there:
Mozilla/5.0 (iPad; U; CPU OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B334b Safari/531.21.10
Easy peasy--now you're done. Head over to Gmail, log in, and you're good to go.
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