The Scroll Lock key was meant to lock all scrolling techniques, and is a remnant from the original IBM PC keyboard, though it is not used by most modern-day software. In the original design, Scroll Lock was intended to modify the behavior of the arrow keys. When the Scroll Lock mode was on, the arrow keys would scroll the contents of a text window instead of moving the cursor. In this usage, Scroll Lock is a toggling lock key like Num Lock or Caps Lock, which have a state that persists after the key is released.
But I also remember downloading stuff from the usenet alt.binaries.pictures.erotica.* newsgroups and needing to edit out the headers, cat them together, and then run the whole thing through uudecode. Good times -- that's partly how I learned vi.
Jeez, didn't your local 7-11 carry porn magazines?
Another case that I'm aware of involved an agreement that a couple made with them years ago, and the IRS recently came back and said, "the agent who made that agreement didn't have the authority to do it.
OK, I'm not a lawyer or anything but.... Doesn't that make it basically impossible to make a contract with anyone? If you at any moment can pop up and say "that guy wasn't allowed to do that"? And that goes for anything that qualifies for a contract, even the receipt you get when shop for groceries. Unless of course the contract in-it-self is illegal.
3: Basic honesty. For almost all home users, MSE is good enough. Getting a commercial AV solution is pointless because most infections end up being 0-day variants that AV products will not catch. Instead, educating the end user on Adblock and sandboxie will go a lot further to prevent calls in the future about infected machines. The $50-$100 that a user would spend on an AV solution can go for an external hard drive (which actually has a tangible benefit to the user) for nightly backups.
And that's the reason why there are very few real "PC repair professional"... Free (price not GNU) AV software DOESNT PUT FOOD ON THE TABLE!
4: Common sense.
This, there is also very little of. But unlike free AV software, the lack of common sense does put food on the table.