Maybe not all renga have been finished. All, possibly, have been begun.
The often several hundred lines of Japanese poetry begin with a set of three. These include seasoning and some cutting, and they're known as hokku — or as haiku, of course.
Part of a haiku's charm is that not one syllable or sound is wasted. Shortmail, now, wants to encourage charming thriftiness for emails, too, and one or the other season word, of course:
›› Shortmail emphasizes easy, fast and effective communication with an email service limited, essentially, to 500 characters per message.