Electronic Frontier Foundation - http://www.eff.org/
From the Internet to the iPod, technologies are transforming our society and empowering us as speakers, citizens, creators, and consumers. When our freedoms in the networked world come under attack, the Electronic Frontier Foundation (EFF) is the first line of defense. EFF broke new ground when it was founded in 1990 — well before the Internet was on most people's radar — and continues to confront cutting-edge issues defending free speech, privacy, innovation, and consumer rights today. From the beginning, EFF has championed the public interest in every critical battle affecting digital rights.
About EFF - http://www.eff.org/about
What you can do - http://www.eff.org/helpout