The unusual thing is that it's die has irregular shape - I suppose this transistor was hand-assembled. Even with some remains of protecting paint on it this transistor worked better than others.
The idea is even older - I've spotted it first in magazines "Zrób to sam" ("DIY") from late '70s or early '80s and "Юный Техник" ("Young Technician").
"Zrób to sam" - solar powered AM radio receiver:
"Юный Техник" - solar (and wind) powered scarecrow. It's solar battery is actually made of diodes (40-60 pieces) with glass packages.