Official rules: No purchase necessary. Beginning Jan. 29, 2014, once a week, Retro Baltimore will post a trivia question at retrobaltimore.com. Enter by answering the question in the comments field (and if you've won, providing your contact information). The first correct answer received by Retro Baltimore wins. Baltimore Sun archives will be the primary authoritative source for trivia answers. The Sun's computer is the official timekeeper. All decisions by The Sun are final. Prize: Each winner receives one (1) Baltimore Sun DigiClean screen cleaner, approximate retail value: <$2. Must be 13+ to enter. Employees of Baltimore Sun and their family members/households not eligible. Further restrictions apply. Void where prohibited.