Way back in the early 80s, when printed meant line-printed, I was asked to modify a huge list produced by our client. The change was to multiply the total values by a factor they would provide, and then print the original totals on the following page. You may be ahead of me here, but I wasn't! They were tearing off the last page for their own records, and using my modified totals to defraud another company. They ended up in court. Glad to say I didn't.