The staff of symmetry has created a fun set of physics-themed Valentines to share with the people you love. And because ours is a universe that contains both matter and antimatter, they've created a complementary set of anti-Valentines, for the people you love to hate.
My favorite Valentine/anti-Valentine pair appears above. The cards are designed for those who "seek to rekindle (or extinguish) a romance with someone intrigued by the invisible elements of the cosmos, such as the yet-to-be-discovered dark matter." The cards come in a few other flavors, including neutrino, LHC, and Max Planck. Check out the full lineup – which you can print for yourself – over at symmetry.