I remember when I was a kid, Caltech students would occasionally hack the scoreboard during The Rose Bowl to change the team names to "Caltech" and "MIT". People would laugh. The thought of an arrest never occurred to anyone.
One of my favorites, there once was a bank called Union Bank in Pasadena. It had a big neon sign that read "UNION BANK" at the top of their building. Apparently a Caltech student was up in one of the unlocked maintenance rooms and figured out the nine giant switches correlated to the letters and changed the sign to read "ION BAN". Nihilism in its purest form.