Google's foray into search personalization stumbled into the great concept of recommendation. By correlating your search history, bookmarks and other data obtained from Google services with other users' data, Google recommends you web pages that might interest you. The first fruit of their work was a Google gadget that initially showed recommended searches, pages and gadgets. Then Google started to show recommended videos and news.
Now the recommended web pages are available in a feed, but also from an URL that sends you to a random recommended URL: Google Recommendation.
If you have Google Toolbar, add this custom button instead. Google's Sep Kamvar describes the magical button: "Click on the dice, and we'll take you to a site that may be interesting to you based on your past searches. If you want another, just click the dice again and we'll show you a new one. We'll give you up to 50 new sites per day that might be of interest."
Google split the all-in-one recommendation gadget into six smaller gadgets for: searches, web pages, news, videos, groups and other gadgets. To get them in your personalized homepage, go to this page and add the six gadgets one by one (alternatively, create a new tab titled "Recommendations"). Here's what I see (click to enlarge):
While this is no StumbleUpon, you may discover a lot of interesting web pages related to your queries you wouldn't have found otherwise.