Humor/Politics/News:
This Modern World (commentary, cartoons & links)
Media Matters for America (correcting conservative misinformation)

Organizations:
Amnesty International
Doctors Without Borders
Operation Truth (advocacy organization for veterans of Iraq and Afganistan

Weird/Groovy/Fun Stuff:
Roadside Peek ("An Adventure in Time")
Forgotten NY ("The Infrastructure of a Lost Metropolis")
Walking in L.A. (unheard of, I know, but this guy does it all the time ... and takes pictures to prove it)
Joe's NYC (NYC street scene photos. He does great work & posts a new photo every day)