The Ethereum layer 2 network went out of service for several hours due to a bug in the sequencer and a resulting transaction backlog that stressed the network. A fix was deployed and the network is now processing again.
The loss in finality meant that blocks could have been tampered with, and while it isn’t supposed to affect end-user experiences, it did lead to some inconveniences for some applications.
The Helium network has two tokens, HNT and MOBILE. Binance counted them as one, HNT, resulting in a windfall for customers who deposited the less valuable MOBILE.