(Edit: Gwern points out in the comments that there is previous discussion on this study at New study on choice blindness in moral positions.)
Earlier this month, a group of Swedish scientists published a study that describes a new type of bias that I haven't seen listed in any of the sequences or on the wiki. Their methodology:
We created a self-transforming paper survey of moral opinions, covering both foundational principles, and current dilemmas hotly debated in the media. This survey used a magic trick to expose participants to a reversal of their previously stated attitudes, allowing us to record whether they were prepared to endorse and argue for the opposite view of what they had stated
... (read 380 more words →)
I have taken the survey.