Since Google doesn't offer an "official" RSS (or ATOM) feed for their Google Zeitgeist rankings of popular search terms, Kunal Anand decided to create one using a "screen scraper" he built with Perl code. Here's a link to the GZeitgeist feed along with some technical details posted on Kunal's blog. On Searchblog, JB wonders if the feed will be around for long since it's a screen scrape.
On a related note, the Yahoo Buzz Index of popular search terms offers a number of "official" RSS feeds.
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