Portal 2's development was full of ideas which didn't make the final game, including a sequence in which protagonist Chell ended up married to a turret. Yep.
Speaking at a PAX Prime 2012 panel, Valve's Erik Wolpaw and Chet Faliszek, the writers of Portal 2, revealed a couple of sequences which didn't make the final cut.
In one, Chell would discover a "lost tribe" of turrets living in the ruins of Aperture Science. Having assisted the turrets in some way, Chell would be rewarded by their king - the giant, jungle-print creature spotted in the ending sequence and in warning videos around the facilities - by being married to a turret dressed as a bride. Valve even modelled the bride turret.
The turret would then follow Chell around. Turrets have never been seen to ambulate in Portal, but Valve apparently intended to have it teleport around behind the player like the famously creepy Watson.
In another cut sequence, players would come across a computer with the mind of Aperture founder Cave Johnson stored in its memory. Although the ageing computer would beg Chell for "death", the player would need to haul the hardware around and use it to clamber out of an environment, leaving Johnson without further hope of salvation.
These revelations were made during a discussion of "Plots vs Play"; GameInformer has a nice run down of what else the pair discussed.