I dont think you have any real magnitude of the nature of what you are asking. Every time you use a credit card, debit card, electronic check, there is a record of everything you bought, from toilet paper to potato chips. The post office or UPS, Fedex, has a record of where every package came from and where it went. Ever filled out a questionaire or survey, for anything? Have a facebook account? Have a friend who has a facebook account? Been in a public place where there are people who have a facebook account? When I call midway to order reloading stuff, they recognize my number, they answer the phone with my name, how can I help you? The computer automatically suggests things I might want to buy based on former purchases. I can be tracked 24/7 through gas receipts, fast food receipts etc. This is routinely done by BUSINESS just for sales purposes, to get advertising to me. They dont need a subpoena, they just need anyone whom is not computer illiterate. I nave worked for a department of state government for 25 years, I had to have drug tests, I have run for school board membership, I fill out surveys at Bass Pro Shops, Golf Discount, I give blood, I donate to my University charity drive.I file tax returns. Any simple datamining program can pull all of this together, and any trained investigator could put together a profile in no time flat, almost like the "Truman Show". The only reason they dont bother is that anyone sufficiently out of the normal will be spotted, do something that people report or wonder about, your nosey neighbor, your well meaning aunt, your supervisor who is mandated to report suspicion. I was noted several years ago because I had a 3rd party bumper sticker. I am sure that as soon as my colonoscopy is scheduled they will immediately know if I am the _ _ _-_ _ _ _ they all thought I was. The rule of thumb is this: if you are in a bathroom in the basement with the lights out, it is surrounded with foil faced insulation, you have a radio tuned to a blank station producing static, and you do not put anything down the drains...... you may be safe. My best defense is that my life is so boring that anyone forced to watch it closely might suicide.......