Electrostatic Jack - Active Algae

Electrostatic Jack is a Topre-stemmed jack-o-lantern encapsulated in a 1U Topre Esc key.
 
Active Algae is thermochromic (changes color in response to temperature).  At 77°F(25°C), the caps change from green to yellow.  This makes them very responsive to touch, sun from your window, etc.