I found something incredibly obscure: a promotional riddle/puzzle/ARG for Absolution that seems to have gone completely under the radar.
Cosmo Faulkner had a fake Google Plus account set up here long before the game was released:
Almost no one went there. Google Plus was always a ghost town, and I only found the page through the hitman wiki.
But a pair of posts from December 2 and December 5, 2011, show a series of tickets and a pair of pages from a tour guide that contain some sort of hidden message from the character, Birdie. I’ve gotten partway through solving the riddle, but I have no clue where it leads!
I am incredibly curious if anyone from IOI who was around when this was produced even remembers it.