This event was like a spark to a barrel of gunpowder and caused World War I to break out. Some people have said that the car was cursed and involved in the deaths of other people, but on closer examination these are urban legends.
After the double assassination, the car was donated to an Austrian museum, where it has been since. It was built by an Austrian company in 1910. The Gräf & Stift is known as a 'double phaeton' and powered by a 23,8kW (32hp) 4-cylinder engine. It was owned by Count Franz von Harrach, an officer in the Austrian army transport corps.
The Austrian army in 1914 apparently had budget restrictions so, instead of a military car, the archduke was provided with a private vehicle. Count von Harrach was with the car in Sarajevo and witnessed the shooting.
Eyewitnesses to the assassination said the Gräf & Stift did not have a reverse gear, which slowed the car in changing direction. This delay allowed the killer, Gavrilo Princip, to approach the car and shoot.
Count von Harrach gave the car to Austrian Emperor Franz Joseph after the killings and the emperor donated it to the museum. Manfred Litscher, a public relations officer at the museum, said the rumour that the car had been involved in other deaths seemed to have come from an English newspaper, although he could not provide more information. It has been sitting in the museum, unused, since 1914.
The car is still part of the museum's Sarajevo exhibit, which includes the archduke's bloodstained uniform.
Gräf & Stift was formed by the Gräf brothers who, like many other car manufacturers, had started out fixing, then building, bicycles. They built a prototype automobile and started production with the help of Wilhelm Stift, a businessman from Vienna.
During World War I the company stopped building luxury cars and built trucks and buses to help supply the war effort. Gräf & Stift didn't start making passenger cars again until 1920, but stopped in 1938.
The company was absorbed by the truck manufacturer MAN in 1971, with the Gräf & Stift name continuing to appear on trucks and buses built in Austria until 2001. MAN then renamed the company MAN Sonderfahrzeuge.
A spokesperson for the museum said the car has not run nor moved since it came to the museum.

Archduke Franz Ferdinand (right), heir to the Austro-Hungarian throne, and his wife, Sophie, shortly before the double assassination.
Sources: New York Times and Wikepedia