From our partners at Buzzfeed: 1. The Zodiak Killer This guy really liked killing people. Active in Northern California for about 10 months toward the end of the '60s, The Zodiak killed at least 5 people, and sent coded letters to the local Bay Area press. Only 1 of 4 cryptograms have been solved. Read more to get the solved encrypted message. 2. The Garden Museum Heist In 1990, two guys dressed as Boston cops pulled off the biggest art heist in history. After conning their way into The Isabella Stewart Gardner Museum, the two men gathered and tied up all on duty guards before stealing artwork valued at $500 million in paintings, sculptures, and artifacts. A $5 million reward for information leading to the recovery of the stolen artwork remains open. 3. The Tylenol Killer This is perhaps the most influential mystery on the list. In the early fall of 1982, seven Chicago-area people died from taking Tylenol that had been laced with cyanide. Following the deaths, Tylenol was pulled from shelves and within six months, federal anti-tampering was put into place to prevent any similar tragedies. No arrests for the murders have been made. Get the full Buzzfeed list here.