I got a close up picture of an exposed die in an optical mouse. As far as I know it's rare to have a die so exposed. But in this application it's necessary as light has to reach the die. The coolest part I think is that this is the only active part in the mouse. So all the processing and logic is done on that bit of silicon. Lastly I pulled a hair from my head (not pictured) and it was thicker than those wires. 
