Google Page Creator, the service that lets you create and publish static web pages hosted by Google, lets you embed Javascript code in the pages. You just have to go to a editable area, click "Edit HTML" and type your script. That means you can include in your pages AdSense, Analytics code, Ajax and other interactive features.
Until now, users had to create HTML files offline and upload them in Page Creator, which was pretty difficult, especially if we think that the service wants to let you "build high-quality web pages without having to learn HTML or use complex software".
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Add gadgets to Google Page Creator