I came across Synthetix.exchange a while back while researching the Synthetix Network Token or SNX. The exchange is really awesome as you can trade a bunch of assets long/short with infinite liquidity and low fees! Go long or short crypto, forex, gold and silver, or even the Nikkei or FTSE stock indexes. They plan on adding crude oil soon as well. Overall it's one of the best trading platforms in my opinion and it's decentralized because you connect with your Metamask wallet and the price feeds use Chainlink oracles. Don't worry if certain pairs have no daily trading volume, as liquidity is infinite. You can always open or close out positions with no slippage. This works because behind the scenes holders of SNX tokens create collateral to back the system and they take on the burden of debt from profitable trades in exchange for a portion of the trading fees. You can learn more about how the system works at Synthetix.io. Overall it's worth exploring even if only to make a small trade or two. Give it a shot!
This is not financial advise. I do hold some SNX tokens so I receive a tiny percentage of all trades on the Synthetix Exchange. That being said, I am invested because I believe in the product and I think it's a great service. If you want to earn trading fees as well, pick up some SNX tokens on Uniswap and head over to mintr.synthetix.io. Let me know what you think of this platform!