Ever since the advent of social media management, Twitter jockeys have been waiting for the brand engagement goldmine that is 21 October 2015.
Why? Because it's the day Marty McFly and Doctor Emmett Brown travelled to at the start of 'Back To The Future Part II'.
Everyone knew it would be the biggest trend of the day, ensuring nobody with an online presence could avoid images of Michael J. Fox and Christopher Lloyd.
Some brands, like Nike and Pepsi, were lucky enough to have their advertising done for them, having been featured in the original film. So it made sense that they would get involved with the hashtags on this landmark day.
Others... stretched it a bit. Like Weetabix, who thought this abomination was worth their time:
And then there was Citroen's oddly worded attempt:
A phone company actually thought this sounded good:
Gregg's jumped in too, but theirs was so shameless it was funny:
And PG Tips, with a genuinely cool-looking monkey:
And remember the chicken restaurant which trained a hen to run their Twitter account? They came out with this beauty:
Don't worry, everyone. A few more hours and this'll all be over.