Emoji reaction systems are a fun and effective way to manage work communication in Slack channels by reducing unnecessary notifications and automating routine tasks. By using specific emoji reactions, teams can acknowledge messages, bring important requests to someone's attention, mark the status of a request, and capture bugs or feedback in their issue tracker. Additionally, emoji reactions can be used to automate tasks such as creating a task list, capturing good ideas or productivity metrics, and coordinating with teammates. By leveraging these features, teams can streamline their workflow, reduce noise, and increase productivity.