Below is a list of manifestos I find to be important and critical to hacking, privacy, and information technologies. They are both directly and indirectly related to said topics.
Guerilla Open Access Manifesto — by Aaron Swartz in July, 2008.
A Cypherpunk’s Manifesto — by Eric Hughes in March, 1993.
The Crypto Anarchist Manifesto — by Timothy C. May in mid-1988.
The GNU Manifesto — by Richard Stallman in March, 1985.