Well I don't know THE most interesting thing, but a new friend of mine said something to me that I found quite interesting the other day.
When you have cognitive dissonance of some form i.e. you hold two seemingly contradictory beliefs, perhaps "I like smoking" and "I don't want to smoke", it is the wrong approach to try and drown one thought out or attempt to abandon it. Instead you should assume that you are a rational being however you do not understand the thoughts you have clearly. Investigating the contradictory beliefs to a deep enough level should eventually come to a point of harmony where you can understand why you thought both of those things. I guess this is a form of mindfulness.
To use the example above, I like smoking and I want to stop smoking does work together when you realise that the want to smoke is more like a preference of colour - something relatively meaningless - and the desire to stop smoking is something with a real practical basis. Therefore by understanding the true nature of these feelings you discover that you are in one case describing something you like and in the other something you want to achieve. It is then clear you should be obviously acting upon the goal, not the instantaneous preference.
Long time ago, trying to save my first marriage, got told, "I love you but I'm not IN love with you." Man at the time that hurt and realize that this relationship was done. Running a crew at a shop, had a couple of young guys out of high school working for the summer, lunchtime, one of them got some food down the wrong pipe and was already turning blue, so at first I thought they were just fuking around (Kids) till someone screamed "He's choking!!" Got up and slapped the DDT (heimlich) move on him and pretty much saved his life. Sat back down as he's thanking me etc. Come to find out he was the big bosses son! He came down and personally thanked me, the kid came back the next day and got me a card for saving his life. I thought that was a pretty cool Hallmark moment.