Voltaire allows users to send messages to a Discord server anonymously.
When Voltaire is added to a Discord server, members of the server can send the Voltaire bot messages which will be relayed to text channels in the server. Once added to a server, Voltaire will send a message to the server with some basic instructions.
Though it does have its pros and cons, anonymity can be a useful tool in the correct context. Well-run democracies have secret ballots for a reason. Whistle blowers can be enabled and community members can express themselves without fear.
... for fun.
While Voltaire does allow anonymous messages on a server and doesn't log any any messages, Discord as platform still does. With that said, not even channel or server admins will be able to see who is sending what.