Its collection isn't exactly what we'd call comprehensive just yet, but one day the Museum of Endangered Sounds could be the de-facto place to go to teach your kids about technologies of yesteryear. Or at least teach them what those technologies sounded like.
Hearing Speak & Spell's cold synthetic voice ironically still brings a nostalgic tear to our eyes. And the Tetris theme still sounds best coming through the mono speaker of the original Game Boy. So when the day finally comes when you need to talk to your kids about the evils of modems and how to recognize one on the street, you can just point them here and let them learn about the world the same way you did—through a browser window.