This is the 3D printed Kraken tentacle D20 available from Nvenom8 Designs' Shapeways shop. You can get it in any color plastic for $15, a variety of colored steel for $45 - $50, or raw brass or bronze for $120. Obviously, metal is the way to go. The designer also states that they're properly weighted, and roll fairly. Is that true? No clue. But if I use one to roll to see how many life points I lose after getting clubbed in the head by a lava troll, AND I DIE, it will be the first time in history a Dungeon Master has every been successfully stabbed with a D20 before.
Keep going for several more shots and a video of the thing being rolled.
Thanks to Goldenboy, who shines so bright I can't even look straight at him which sucks because I'd love to break one of his arms off and sell it to a pawn shop.