Nav/Radio froze up and/or crashed

Maybe 'crashed' is a bad word when you're talking about cars. But something like that happened.

I started it up in the morning to make the drive to work. The nav screen looked funny when I hit the 'I promise to watch the road' button on the touchscreen. The lettering on the button was washed out - not black like normal. I didn't pay much attention until a little ways up the street, because my iPod Touch still hadn't connected to play my usual accompianment for the drive to work, the podcast "Keith and The Girl." Instead, all I heard was silence. The map was tracking my drive. I clicked the AUX button. Nothing happened. Then SETUP. Then SAT. And so on. Nothing was responding.

I was continuing to drive, but now I was violating the spirit of the button I clicked a while ago. You really shouldn't troubleshoot something like this and drive at the same time. For the next fifteen minutes, I tried holding the power button on the unit for over ten seconds. Pushing multiple buttons at the same time. Pushing all the steering wheel controls. Using my Bluetooth cell phone to make a call -- no response or connection to the head unit. Powering off the cell phone, and the iPod to break any potential Bluetooth connection. Messing with the AC and fan controls. And touching everywhere on the touchscreen.

Through all of this, no response from any part of the head unit. It continued to track the drive to work. In silence (the Prius can be really quiet sometimes).

I drive past my dealer on the way to work, so I pulled into the service bay leaving the car 'running' so they could see the condition it was in. One of the customer service guys got in and saw how it wasn't responding, and said he'd be back with a real technician. Instead I got the service manager. He got in the driver's seat and immediately shut the car off. Oops?! When the car turned back on, everything was fine, of course.

They booked the event into the service computer, and said they'd check with Toyota to see if this is a problem. It's only happened to me the one time. Anybody else see something like this?