In the late 1960's, a man who called himself The Zodiac Killer, terrorized the residents of Northern California. Five random people were identified as being either knifed or shot to death, and The Zodiac, himself, claimed to have killed even more.
The Zodiac Killer craved publicity, and like the Washington DC Sniper's, taunted the police and public, including threatening children. Even after the killings stopped, the letters kept coming, until 1974.
Although more than 2,500 people were considered suspects in the case, it is still not know if the Zodiac Killer is alive or dead.
As of this writing, the police still receive tips from the public nearly every day about The Zodiac Killer.
Another website featuring known Zodiac information:
Zodiac Killer - The crimes, victims, and suspects