Folks, FYI , "shredded" documents can be put back together.It is not fun,not fast, but you can do it.Important info is typically shredded,then burned.Less important info is just burned.A typical cheap straight cut document shredder is useless to a determined info gatherer.
Fire! First choice for document destruction.I guess California must have a lot of emission restrictions.hehehehe.
The difficulty of reassembling shredded documents is more or less proportional to the square of the number of pieces and inversely proportional to the size of each piece. Straight-cut shredders are pretty lousy on both counts; cross-cut shredders are much better, but document reconstruction may be possible unless a very large quantity of shredded documents are all inter-mixed. Even there, I would suspect that there may be enough clues to substantially reduce the difficulty from O(N^2) to O(n). For example, some printers which have not been cleaned leave a very faintly noticeable pattern of periodic smudging as they print. Such a patter would allow pieces printed of documents printed on the same printer to be grouped together, and would also help considerably in locating where each piece is supposed to go.