When I've seen mastodon in one of the titles for the first time here I was surprised, because I thought that one of my favorite bands are being discussed here.
To me the most obvious one is sharing economy without a completely useless money grabbing central authority (see virtually any popular sharing economies like uber, lyft, airbnb etc). These all can be created in a decentralized manner with blockchain tech, especially Ethereum.
It wouldn't be that hard in this case. You just have to watch for an address holding stuck ethers because of the bug, if the ethers move, it is a proof that a fork has happened.