A very neat hack. Now it could be used for other purposes, for example, I could ignore social sites and look at other major sites (e.g. I could see who goes to CNN.com vs. FoxNews.com). Or a company could see which of its competitors a visitor has visited.

Also, it would probably be possible to recurse on a site and figure out what pages they are visiting. For example, suppose a top-level detect shows that I visit reddit.com, the system could then load up a reddit specific page and discover that I also visit reddit.com/r/funny. I would imagine that for some sites that could be very revealing.

wow, that's pretty clever. It uses CSS link-coloring to figure out if you've visited various sites.

I didn't realize that works.

As a very active social bookmark user I don't need 'help' bookmarking your site, I already have browser plugins, toolbar links and plenty if incentive to bookmark if I find your article/site/page useful.

Most people are lazy though, and if you can get a few votes from the lazy/indifferent, then you are more likely to end up on the front page (and get all that ad revenue or whatever).

That said, I've gotten to the front page of delicious and reddit without stupid tricks like this. I just wrote an article that people liked. (What a concept.) I don't have ads either.

It's a great find, but a huge security hole. The browsers have got to patch it, even if it breaks some CSS functionality.

Very true. There is a a lot of potential for abuse of this kind of thing.

I heard about this technique a while back in a presentation about javascript malware: http://www.spydynamics.com/spilabs/education/presentations/J...

.. there's a whole section on stealing browser history and how to figure out a user's search history.

Very cool. I was thinking this would be some type of cookie hack. This is pretty clever tho.

I'm not positive on the overhead for this. Loading a couple of links in an iframe shouldn't be too expensive.

But if it were a problem you could easily create a solution to store these settings in a cookie, so the iframe would only be loaded once.

That is pretty awesome. I was just about to write the social bookmarking code for my new blog engine... this is excellent.

Or: How to freak your visitors out