The US Census Dept is conducting "The American Community Survey". This is interim, something other than the usual ten year census. It was done in 2005, and now a follow-up in 2007. There is statutory authorization for it. Selected citizens are required to complete it under penalty of heavy fines. Should you ignore it, you will be hounded (I have been) by intimidating callers from the Census Dept.
The survey is intrusive: in addition to name, address, persons living with you, job, education and similar census type questions, it requires date of birth, income, break-down of income, mortgage payment, electricity gas water and sewer bills, ethnicity, languages spoken, health, eyesight, hearing, disabilities, time you leave for work, and much more. The survey form says it takes an average of 38 minutes to complete the form; it is long. But more than taking one's time, is the nature of the governmental intrusion. What are these for? How do they relate to census needs? Isn't that for reallocating Congressional seats? How does my income, water usage, mortgage payment, eyesight, or time I leave for work relate to any legitimate governmental purpose? Why would Congress authorize the executive branch to pursue such info about citizens? Does the right to privacy mean anything?
Usually when the government intrudes upon privacy--requiring schooling, military draft, auto licensing, requiring filing tax return, jury service, airport search--the public need is evident and the alternative not pretty. The given justification for this survey is the vague so Congress can better address national needs. If such justification is enough, privacy seems meaningless.