Check it out: a real nickel that’s been cut in half and hollowed out, so you can hide a Micro SD card inside. It’s been dubbed a “spy coin” (although it doesn’t really do any spying).
I guess what interests me about this is the fact that you can easily hide many gigabytes of data inside something as innocuous as a nickel. We’re a long way from room-sized disk arrays that held a few megabytes…