There are implants which are purely aesthetic, and then there's the Digital Tattoo Interface concept. It's a blood-powered electronic interface which is embedded under skin to mimic a tattoo, display videos, or act as a phone or computer.
As great as it seems, this concept is seriously creepy because it powers itself by converting the glucose and oxygen found in blood into electricity. Though somehow getting your blood sucked by a gadget is worth it for the endless potential applications. I'd probably just end up using it to moderate comments, but what would you do first with your implant? [Core77 viaGeekologie]
This week, Gizmodo is exploring the enhanced human future in a segment we call This Cyborg Life. It's about what happens when we treat our body less as a sacred object and more as what it is: Nature's ultimate machine.