In my group of friends/family, I'm usually the go-to guy for anything that people deem tech-related, from cell phones to the Internet. When people ask me for help, I try to explain things and empower them, but I don't always get the impression that they understand the fundamental issues at play or even care to find out once they are able to get the device to do what they want it to (or in one-time cases like setting up a network, once I do it for them). At that point, no clever analogy or metaphor is going to educate them.
The problem with this is that when their network has "limited or no connectivity" or Windows doesn't boot, they need me to help them again.
Luckily for me, being a programmer, this sort of thing isn't my job, but I was wondering how you sysadmins and IT professionals deal with the tricky issue of explaining things to laypeople.