Do you like bananas is taken from a youtube video known as "Friendship is magic Bitch"(Credited to Skaijo) It entails The Princess of the ponies listening to her subjects complaints and interrupting them and making them admit their opinion on bananas. Once it is clear on their opinion They are launched to the moon. It is notable for being able to derail a thread by intrusively asking if someone likes bananas, until the other person posts their opinion on them the poster will persist. Its fairly popular among the brony community and is used frequently on ponychan.