Want everyone to use your software? Make an idiot-proof box. All successful and disruptive technology has one. I’m not sure why this is such a hard lesson for many companies. Idiot-proof boxes need zero training. People are busy and stressed, just give us our idiot-proof box and keep our heart-rate and time to a minimum.

Winner of the most disruptive idiot-proof box has to be Google.

Email’s idiot proof box is “send,” although it’s also the winner of the worst idiot proof box, “reply all” (the scariest button on a computer).

Instant messaging has had the same UI from the beginning. Here’s your idiot-proof box: write something and we get it instantly.

Twitter took a page from Instant messaging book but put a cap of 140 characters on they’re idiot-proof box. “Tell us what you’re doing, just keep it short, we’re busy.”

Blog and wiki software’s idiot-proof box is the “publish” and “edit” buttons, respectively.

YouTube’s explosive growth is connected to their idiot-proof box. Just cut and paste.

Firefox’s idiot-proof box is their tabs.

I just joined Seesmic yesterday and their idiot-proof box seems to be their red record button.

And then there’s the iPod. It’s idiot-proof box is more of a wheel but it changed the whole company’s destiny.