The story of why they sing the Boar's Head carol at Queen's is quite interesting(well, I find it quite interesting anyway).
Queen Philippa, wife of Edward III and mother of the Black Prince, founded the college. And it was specifically set up to cater mainly for students from Cumberland and Westmoreland. At Oxford, it was the usual thing at Christmas for the colleges to shut and the students and fellows would go home and visit their families; but this was in the 14th century, before the building of the M6, ands winter travel in the far north was not a doddle. So the Queen's College uniquely stayed up at Christmas, and celebrated together. They had a Gaudy(feast) on Christmas day, and the Boar's Head carol was sung each year as they carried in a roast boar's head with an apple in its mouth in the old way. And that custom is carried on till today each year; though with better transport people can go home for Christmas, so the Gaudy is held a few days beforee Christmas now.
Another nice touch is that the Black Prince's hunting horn is passed round full of booze as a loving cup that everyone drinks from, after the food is finished. We used to sit and smoke free cigars too, but in this more censorious age the young genetlemen(and ladies even!) have to go outside into the quad to smoke. With the current practice of filming everything on mobile phones I expect you could even find a video of the Boar's Head processional entry, but I am not going to look. This is a secret rite as far as I am concerned.