Bulgari just unveiled a watch that hides itself behind money. Not metaphorical money, but an actual ancient Roman silver coin, minted somewhere between 198 and 297 AD, graced by Emperor Caracalla. You flip the coin up, and there’s a dial underneath. Flip it down, and the watch disappears into history. The whole thing is called the Bulgari Maglia Milanese Monete Secret Watch, and it costs €157,000....