I'm not that into social bookmarking sites, but I just came across Stumble Upon .  It's sort of like hitting the "I feel lucky" button on Google, except for the sites you find are completely random.

 Okay, so not totally random.

When you register at Stumble Upon, you select the topics that you are interested in for your profile and install a toolbar for  your browser.  A random site in one of those categories is displayed every time you hit the "Stumble" icon in the toolbar.

 The cool thing is that you find sites you never would have otherwise.  It's also very addicting.

 My Favorite Site of the Day:  Nikal.com   

It's the online equivalent of dropping dye into a glass of water and watching it swirl. 

 Try it and see.  Flash required.

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