While returning to Headquarters on Oa, a very old Power Ring passes by a very strange planet. There it discovers its new Green Lantern, a young lad named Mat Cauthon. A Wheel of Time (book) / DC Comics (one character only) crossover.
In 1727 the Prime Minister Robert Walpole appointed a squib named Sir Isaac Newton as the new Headmaster of Hogwarts. By the time Harry Potter arrived there in 1996 the academic curriculum had changed a bit.
In the year 2980 a team of archeologists discovers a secret autobiography written by Harry Potter, the Great Seeker who brought peace and prosperity to the world. It paints a very different picture than the one found in the official history books.
The blood wards around Privet Drive have a disastrous effect on Harry Potter's magical development, leaving him unable to use a wand. But there are other kinds of magic, and other paths to power. Harry/many witches. No horcruxes.
After the war is over Harry wants to protect his godson Teddy Lupin, but he isn't sure how. Mrs Tonks has a few interesting suggestions for him. A Harry/Luna/Andromeda story.
Five years after his defeat the shade of Voldemort visits Harry Potter, and has a slight accident with one of his Horcruxes. The Dark Lord wanted a new body, but this isn't what he had in mind.
Before her death Sybill Trelawney makes one final prophecy: Harry Potter must leave the Earth, and find a new home for his people around a distant star.