More generally, imagine a corpus which could identify the conversational function of a sentence, such as, "Have a nice day!", in narrow categories like, "ending a conversation", or broad ones like "small talk", and then produce lists of other sentences in the same categories.
Does anything remotely resembling this exist?
Other interesting categories would be, phrases often used in emails, phrases occuring often in business discourse, different ways to apologize, casual ways to greet people, and so on. Even an encyclopedic document of human-curated lists would be valuable, but an oceanic corpus would be far better.