Synthetic dollars, in fact, can cost more than “real” dollars because it is necessary to overcapitalize their collateral to avoid the risk of losing that alignment with the US dollar. Despite these risks, quite a few blockchain-based digital assets have been established with a peg to the US dollar. MakerDAO's dai is probably the most successful of these, although its current backing includes some US dollar assets. However, there are others that are tied exclusively to cryptocurrencies and other digital assets that are not connected to the dollar.