I think the test of the importance of your work is not how much people will be hurt if you screw up, but how much people's lives are improved if you succeed.

I notice you leave out the Manhattan Project. Through which nuclear power was discovered. And later those same researchers discovered Quantum Electrodynamics... which will likely be the next hardware solution for computer science.

Judged by the standard of how much it contributes to people's well-being, Google probably does more for the world than the Apollo missions did.

As for Apollo versus Google - come on. Search (PageRank) & improved web mail (GMail) versus safe commercial air travel, radio and satellite communication, safe structures, better roads, GPS, etc. Maybe there weren't advancements to Computer Science. But, there were major advancements in civil, construction, electrical and mechanical engineering.

The program spurred advances in many areas of technology peripheral to rocketry and manned spaceflight. These include major contributions in the fields of avionics, telecommunications, and computers. The program sparked interest in many fields of engineering, including pioneering work using statistical methods to study the reliability of complex systems made from component parts. The physical facilities and machines which were necessary components of the manned spaceflight program remain as landmarks of civil, mechanical, and electrical engineering. from http://en.wikipedia.org/wiki/Apollo_program

Separately the Apollo program had a cultural impact on the students and engineers of the time and even today. I know I am inspired by what the program did with such limited technology.

[EDIT: Some details and another quote]

For some reason, this excellent comment reminds me of my visit to the sewers of Paris (they've got a museum down there!)

There's a quote from Napoleon in which he proclaimed that the redesign of the Parisian sewer system (which was commissioned during his reign) was one of the most important things he ever did. It's surprisingly hard to argue with that.

I have no idea. This whole conversation seems like a big tangent, and perhaps I'm having a bit too much fun following it off into infinity. Shame on me.

Anyway:

Yes, Boeing has a more difficult task than many startup founders. Of course, there are also more engineers at Boeing, and they've been working on the problem for a much longer time.

Yes, it would be possible for a Google or Facebook design error to get someone killed. Leaks of personal or financial information are potentially deadly. Bad information can be deadly.

No, I can't give you a specific example of a design error (as opposed to a user error) that killed a Google or Facebook user. That's partly because Google and Facebook engineers -- like Boeing engineers, and most engineers worthy of the name -- take their work seriously and don't make many consequential mistakes. But mostly it's because our standards are looser, and reasonably so: The internet is a twelve-year-old invention, and when planes were twelve years old people crashed and burned all the time. They were experimental, and nobody expected anything different.

Standards will change. We're hearing stories of users who followed a Google map off a road and are now suing Google for damages. Right now those stories serve as hilarious examples of lawsuit-happy, stupid people, but perhaps in fifty years middle-class people will expect digital maps to be perfectly accurate, just as today they expect to have clean water and lead-free plumbing, and to always be able to reach an operator by dialing 911 on their cell phone.

Finally, I don't think this sentence is correct, in general:

The fact that people misuse something doesn't make it the engineers fault.

The problem is that there's no bright, shining line. Your kitchen knife example is far to one side of the line: Because kitchen knives are a very well-established technology, most knife accidents are caused by people misusing the product. On the other side of the line is, say, food that's been sweetened with ethylene glycol. That's pretty obviously a design error. And in between is a huge grey area, in which most software falls. Is Boeing responsible when a confused pilot pulls the wrong lever and fails to lower the landing wheels? [1] Is the guy who built the buggy online spreadsheet responsible when the civil engineer uses it to design a bridge that falls down? Well, that's why we have courts -- and why your startup needs to have a lawyer.

[1] I do know that planes used to have a little wheel-shaped lever to guard against this very problem. Maybe they still do. I forget where I learned that -- was it from Donald Norman?