You can PM, or post on Global to set a reminder. <code>#remindme</code>, <code>#remember</code>, <code>#reminder</code> can all be used with [time/interval] [optionally <code>-pm</code>, if posting and you want the reminder to be a PM.]
In a PM, you can also ask say <code>show reminders</code>, and it will show upcoming reminders.
You may also manage what chat rooms @reminderbot is watching/subscribed to, with the commands <code>rooms!</code> (shows currently watched rooms) and <code>[un]subscribe! [room ID]</code>.