This impressive tattoo looks like a dial home device (DHD) embedded inside a stargate riding atop a turtle. Its owner writes:
I put the Stargate SG-1 gate around the perimeter with a DHD in the middle. The gate address for Earth is highlighted in orange on the DHD portion. The Stargate is on the back of a turtle for 2 reasons. My son loves Turtles and various cultures and mythologies believe the earth is riding on the back of a turtle through the universe so it seemed a good tie in. The Stargate wormhole effect surrounds the Turtle.
via Geeky Tattoos