BitBay is developing a decentralized marketplace based on a non-colateralized stablecoin. Unlike other stabelcoins, BitBay is stabilized with a dynamic peg that is meant to reduce volatility without anchoring the price to another asset. The network has a Proof-of-Stake (PoS) consensus mechanism.

Gold Bits Coin is developing a digital currency that is backed by gold. They hope to create a digital asset with less price volatility that can be used as a medium of exchange. GBC is built on Ethereum. Their marketing materials are unclear about how much gold they have in reserve to back each Etherreum-based token.

The Maker token (MKR) is the MakerDAO native token. It acts as a utility token, governance token and a recapitalization tool for the MakerDAO platform, which manages the DAI stablecoin. MKR is used as part of the stabilizing mechanism that is in place to combat the price volatility of the DAI stablecoin.
DAI is pegged to the US dollar and has collateral in place to ensure stability. The MKR token is used is to pay for the "collateralized debt positions" (CDPs) that have been used to generate DAI. After this MKR is used, it is removed from the supply. MKR holders also contribute to the governance of the MakerDAO and vote on crucial issues related to the direction of the DAI stablecoin.