As you may know, El Al doesn’t screw around when it comes to security. To that end, El Al has installed anti-missle systems in all of its aircraft, becoming the first carrier to do so. The Israeli-built system, called Flight Guard, releases diversionary flares if its sensors detect an incoming missle.
Development of the systems, which cost about $1 million a piece, was put on the fast track after al Qaeda attempted to shoot down an El Al aircraft in Kenya back in 2002.
According to the linked article, we shouldn’t expect many other airlines to jump on board with this. On the other hand, the chance of an aircraft going down because of a missle attack is incredibly remote — a DHL A300 cargo plane was struck by a missle in Baghdad in 2004 and landed without incident (well, getting hit with the missle was an incident, but the landing was not).