At oomlout we firmly believe electronics can be beautiful, inside and out. We've previously highlighted some historical images showing what's hidden inside integrated circuits, and watch with awe the work of Russian research and development outfit ZeptoBars which, in the company's own words, spends the weekends "having fun dissolving microchips in boiling acid" and taking pictures of the result. Most recently, ZeptoBars published an image that caught our attention: a shot of what's inside the ON Semiconductor P2N2222A transistor we sell as a bundle and include in our Arduino ARDX Starter Kit. Used for switching higher-current loads than an Arduino can handle directly, transistors are common components that hide microscopic complexity. We'll certainly be keeping an eye on the ZeptoBars blog to see if any of our other stock features - and we'd recommend you give the company a follow as well, if electronics is your thing.
Comparing to NXP BC847B die area is 1.5 larger (0.118 vs 0.076mm²), but maximum continuous collector current is 6 times higher (600mA vs 100mA, SOT-23 in both cases).