An article on Wired says a school district in Philadelphia was caught spying students by using LANrev, a MAC-based asset management software on MacBooks for high school students, which was preinstalled on each of the computer and was supposedly used to track the device and recover the equipment in the event of theft.
The laptop usage policy explicitly stated the users could not modify the loaded software in any way, nor could they use another laptop while in school or leave it at home. So even if the students found out the presence of the software, they coul not remove it anyway.
Needless to say, a public outrage burst out, the IT staff were blamed for the whole scandal, and the lawsuit is seeking a class action against the school district.
Moral lesson? Never trust a computer you can't throw out a window. (Ironically the quote is attributed to Steve Wozniak, co-founder of Apple...)