Except that the space is never not filled. 0 is a valid address. The certificate means we haven't figure out how many apples you have yet.

1. Do not belittle or otherwise blow off the customer's fear. In fact, hear it, and agree that it's something to think about.

Them: "I'm worried about this Linux stuff. A guy was telling me that anyone could see the code, and just know how to hack it!"

You: "I can understand how that could be a concern. It is a little like having a map of the valuables in your house taped to your front door."

2. Explain why openness is helpful

Them: "Yeah, so what should we do?"

You: "To be honest, sir, the reason why we like that anyone can see the code is because that means anyone can fix those problems. And lots of people do, for the very same reason you are worried about it. They need something that's secure, and isn't going to surprise them."

3. Mention that serious people have a big stake in making this work.

You: "I should mention that a few companies have bet a lot of money on open source, and wouldn't be happy to see it easily broken. IBM, Novell, and Oracle, to name a few, have very large investments in Linux, and have donated many patches to make sure the code is secure. And for that matter, so has the NSA. They have actually extended the security quite a bit, with their Security Enhanced Linux."

4. Reassure them that people are thinking hard about this.

Them: "Yeah, but if anyone can see it..."

You: "...then you have to be extra careful. See, the strategy that Open Source follows, and everyone should, is to assume that everyone *can* see the code, so you better design it so that the real keys to the kingdom aren't in the code at all. You make sure the keys are completely in the hands of the owners of the system, so it doesn't matter if you can see how the lock works, you still don't have the keys."

5. Point out the obvious.

Them: "But what happens if someone tries to slip something in, and is really good at it?"

You: "Once in a while, someone tries. But when a thousand people might look at the files you are trying to sneak in, someone's going to notice. And then a hundred thousand geeks will make fun of you. In public, all over the internet."

There is that, but let's give the waitstaff their due: Trying to do refigure a split check in the middle of a busy dinner is like trying to do your taxes while being pelted with gobbits of cream cheese by taunting girls scouts carrying yappy dogs barking Jingle Bells.

Cut them a break, and let a pocket calculator help.

Making a wry comment based on someone else's poor interpretation of an article: $0.02.

Making a joke in a cliched format you didn't invent: $0.00

Reading the damned source article all the way before you make a fool out of yourself in public: Well, I wouldn't call it priceless, but something like that.

The patent describes a device for accepting credit card payments at the table of the patron, allowing them to pick their amounts paid, and therefore saving the patrons and the waitrons from the hassle of communicating all this back and forth and dealing with the subsequent mistakes.

I think the question to ask is what would bring her the most joy, which might be the thing that challenges her. She should try a little of everything, and find the thing that engages her, makes her feel alive and driven.

I'd suggest looking into Howard Gardeners Multiple Intelligences writing to get an idea of the scope of the situation.