Helen A.S. Popkin for MSNBC:

He had the means and the opportunity, but we may never know the motive of an 11-year-old student who urinated on a couple dozen laptops left unattended at Upper Allen Township Elementary in Pennsylvania.In a report now bemusing Mac fan forums across the Internet, the Upper Allen Township Police Department states that “the cart and computers were damaged beyond repair, resulting in the loss of over $36,000.”

Apparently such “accidents” are not covered under warranty by Apple, which won’t touch them because they’re now biohazards.