With the latest Google Dashboard Widgets announced for Mac, google revealed also a hidden feature in Google Search History which is the availability of RSS.

Widget.feed = "http://www.google.com/searchhistory/find?zx=" +
randomString() + "&num=50&output=rss&client=google-mcsmhwidget";
...
var url = Widget.feed;
url += "&start=" + Widget.resultsStart;
url += "&q=" + encodeURIComponent(query);

If you see the URL, you’ll notice that the only difference with the default url is the output=rss. Notice that to get this feature working you have to login in Google Search History first, because it’s using a cookie. With some investiguation the feature of RSS is also available for Bookmarks. Amazing Google no ?
Via Persistent info