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I am not sure that these are "unknown" so much but here are a few things:
I often go to Matt Strassler's blog here: http://profmattstrassler.com/ Where he talks about current events in physics.
I also used to go to http://www.quantumdiaries.org/ but they stopped updating as much.
Hack A Day always has some cool stuff on there http://hackaday.com/
This is a little bit cheesy but it often helps to get me recentered it's sort of a just a meditative thing: http://thequietplaceproject.com/thequietplace
The Feynman Lectures http://www.feynmanlectures.caltech.edu/ I actually own this series but sometimes I enjoy looking at them online.