This quote from Mark Bowden's book Worm: The First Digital World War – a book I haven't read but  sounds very interesting so I'm going to get myself a copy – comes via Rex Hammock's blog:

Mark Bowden describes a phenomenon called “The Glaze” that “every geek has experienced” when talking about technology with a lay person: The unmistakable look of profound confusion and uninterest that descends whenever a conversation turns to the inner workings of a computer.

If you change the end of the sentence from "a computer" to "my job" that sentence perfectly describes the look on my family members' and friends' faces whenever I talk about work. There's a reason I've earned the title "King of BS (Boring S***).