You know what'd be really good? A gateway between UBB and Usenet. If you post with a newsgroup client, it gets mirrored to the group; if you post to the board it goes out to the group. (I guess this is like the way the xmlrpc discussion group is synched with an email list.) You'd only need only utility: It would understand NNTP and feed news in to Usenet (or even operate outside Usenet but using the same protocols on a different network), and you'd need drop-in modules to understand different brands of bulletin board.
Face it: News clients have had decades of evolution into applications that are powerful, easy to use, and easy to read. Newsgroups handle threading and so on extremely well. Plus, messages you post in are written using a dedicated editor (often an email client) which is so much better than using textforms. What's not to like? Now I just have to write it.