Luna Lovegood

• Dear Aunt Snape (Harry Potter) by Marginaliana
  Snape's words reach more people than he'd counted on when he is recruited for The Quibbler's new advice column.
• The Case of the Unwelcome Owl (Sherlock/Harry Potter) by FayJay
  'So,' said John, feeling out of his depth once again. 'An owl.' It was the same mild, politely curious tone of voice with which he had previously found himself uttering such things as: 'So -- three bags of frozen AB negative,' and 'So -- a selection of human ears.' Goodness, John, with deductive prowess like that you'll soon be putting me in the shade,' Sherlock said tartly. 'Can't sneak anything past you, can we?'
• The Ethernet Chronicles (Harry Potter) by Pythia Delphi
  Post Vold-War II, the Wizarding World has adopted a new-fangled notion: blogging!
• Luna's Hubby (Harry Potter) by MeteoricShipyards
  7 year old Luna wants a husband, and she wants one now. With the unintended help of her befuddled father, she kidnaps Harry Potter. Idea and 1st chapter by Roscharch's Blot

Chivalry

• (2) The Poor of God (Harry Potter) by Branwyn
  After Snape's visit to Surrey, Harry writes a thank-you letter that triggers an extended correspondence and a tentative friendship between the two of them.