Genie Wishes were optional features of /oat/ on Ponychan and MLPchan. They were activated whenever a poster obtained a post number ending in '777'. This would prompt a poster posting as the Genie from Aladdin to appear and grant them a wish. Because of this, the number combination is often referred to as 'wish trips'.
There have been many offshoots from this general idea, ranging from deviantai's 666 'Devil Trips' and subsequent stealing of souls to the 888 'Jafar Trips' on MLPchan resulting in a poster's transformation into an anthro.