This kind of art is also called Silicon Art or Chip Graffiti... its similar to the
software easter eggs 
, only its not software, but integrated inside the IC by
photo-lithography! The engineers who designed those, must also be artists with a huge sense of humour.
They must have known all along that very few people are going to peep inside a microchip and find their artwork.
6) A camel in a Sequent motherboard!.
7) The Christmas Tree bearing the spirit of happiness was resting peacefully inside a Micronas MSP3450G chip.
8) This beautiful Land-Shark, was dreaming about Candy grams hiding deep inside an Analog Device AD1939.
9) this antique automobile was cruising along in an NMAH chip.
10) A toon frog playing a guitar and singing silently inside an Analog Device2175digital-signal-processor.