Let’s suppose you have a new never opened Apple Newton MessagePad 120 and you want to figure out whether the batteries are inserted into the device. How do you do this? Yes, you do x-ray examination.
X-raying vintage handhelds
This Hewlett-Packard HP 100LX is still used on a daily basis
I met the owner of this device few days ago. The guy told me that he repaired this device by himself, and now uses it for programming microcontrollers. He writes programs in C and Pascal. The main advantages he mentioned were small size and extremely long battery life.