If you have ever subscribed to a mailing list that uses MM you would know about the concept of threads-- keeps ensuing replies woven in a threaded fashion making it easy to keep track of communication in a single flow. G has implemented the same concept as "conversations" for gmail users.

However, on most lists there comes a point in time when not every mail that is sent to the list is of interest. On some lists the threads run into hundreds of replies (err...flames if you must) and sometimes after the first email the ensuing "+1" and "yeah, I agree" top-posts will have you clicking the delete key.

Another alternative that many people use right now is the "digest mode", which just lumps all threads and mails it out to you each day. This is not without problems: It creates a different subject line that mucks up a reply in the archives, if you didnt take care to insert the "Re: " before the existing subject line with proper spacing. Even then it can sometimes break the thread in the archives and if you want to search the archives its yet another nightmare. Another problem is with archives which are stored in a monthly archive format but your conversation that started in January may continue into March. If its public mailing list then gmane or google comes to your rescue, else tough luck.

You dont have much choice when a default MM installation will not let you unsubscribe from a thread. Even gmail does not let you do this on google groups (that is another can of worms for another day) but currently in MM  you only have the option of deleting the uninteresting emails, digest or unsubscribing from the list alltogether if there is too much OT chatter.

But what if you had the option to mute by unsubscribing to an individual thread without leaving the mailing list alltogether? Dlist has a feature whereby the user can choose a particular thread or conversation that is interesting to participate, To continue an existing conversation you would continue with your reply by using the email "listname+SampleSubject@domain.tld" and to unsubscribe from a single thread use, "listname+SampleSubject+unsubscribe@domain.tld". To start a new conversation, you would type 'listname+new@domain.tld' as opposed to the old method of emailing the list 'listname@domain.tld'.