After a Federal Judge mandated Apple unlock the San Bernardino shooter’s iPhone, they accidently found the passcode. It was 6969.
Apparently, while the FBI searched Syed Rizwan Farook porn history, his favorite category was granny sex, his second favorite category bestiality, but his third favorite category was 69. With that logic, they tried 6969 and it unlocked.
69 is a sexual position where both parties perform oral sex on each other. It can be done lying down or standing up.
The FBI were concerned that if they tried too many combinations, the iPhone would become a brick and would be hard to retain any information. After a day-long meeting, the FBI decided to try 6969 with success.