Google has some more information about Gmail Labs available.
If Gmail Labs doesn't appear in your Gmail account, please try updating to the latest version of your browser. For the best experience with the gadget, we recommend Firefox 3.0+, Internet Explorer 7, or Safari 3.
If you're using Gmail in a language other than US English, it may also be worth trying to switch your Gmail language setting to US English, and see if Labs is enabled.
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