My girlfriend's father had a hacker break into their network drive, encrypt all their files, and extort the company for $500 of Bitcoin in exchange for the password...
edit: C'mon, folks. Cryptolocker isn't a bunch of hackers targeting individual network drives. It's spread via email. http://en.wikipedia.org/wiki/CryptoLocker
Cos' that's what I see you saying.
No one in the general public is going to know how to protect against "hackers". "Don't open attachments if you aren't expecting them from someone" is actionable advice.
This may not be a correct interpretation of your post but it is how it reads to me, above the edit.
To explain the joke... companies spend tens of thousands doing "pentesting" to stave off vectors for concerted attacks. In this case, they would be spending tens of thousands to prevent the...$500 being extorted. My joke is that it is just as easy to pay the guy $500 for finding the errors. It's just a joke, though. You shouldn't pay extortionists a dime. (Even if that's all they ask for.)
Possibly set-up a periodic cycling system that drives the intruder to move them now, before they get cycled and might lose their bounty forever.