Gmane – is an interesting project that provides archiving and comfortable interface to a huge number of mailing lists. What they do is subscribe to a huge number of mailing lists, receive and index messages. They also provide archives over web and NNTP (news). And they even allow to post without subscribing to mailing lists (they do use one-time confirmation though).
Sounds good? Add to that that the service is totally free, and it willsound even better than good.