Apparently, there's an easter egg in Assassin's Creed 4: Black Flag that makes reference to Watch Dogs, Ubisoft's other open world game which was originally due out in November before being delayed until 2014.
The easter egg, spotted by YouTuber "MrSkillToKill2," is found in an email from Abstergo which references Blume and CtOS, the company and security system in Watch Dogs. For those unfamiliar, CtOS (Central Operating System) is a computer software that controls the city of Chicago's entire information network in Watch Dogs. In that game, Aiden Pearce will be able to hack into electronic devices to access CtOS and use it to control the entire city's security system, disrupt communication, and gain acccess to peoples' personal data.
The email in Assassin's Creed 4 actually talks about this system and provides a brief overview of its capabilities. Check out the video below for a look at the in-game email which makes reference to it.
