Echoing thanks for this thread!
I'd mistakenly powered my Pi down while multiple OSes were /first installing/ from NOOBS. Not good I'm sure! I'd selected more than one for install, including Arch and Raspbian. When powered back on, Arch came up in console mode withe the word 'alarm' in the login prompt. This can't be right.
So I googled "raspi reset noobs," which brought me here.
My keyboard and mouse is a very nice looking wireless set from China via Adafruit, but it has no name, and no model number. It has a one very small wireless USB receiver dongle that picks up both the keyboard and mouse.
So I tried this, and it worked:
* Shutdown the console mode Arch that was running
* Disconnected power form the Pi
* Moved the wireless USB receiver dongle to the upper USB port
* Held down the left SHIFT key
* While keeping that SHIFT key down, plugged power back into the Pi
* Waited while the video initialized
* Success: Up comes the NOOBS install screen!