WBL is a system for ringing bells over the Intrnet with other people. A wbl server runs on oussik.com on port 5345. To connect to it you need a client. A list of clients you can try is listed on the left menu.
If you want to run your own server, get the sources and compile your own server. You are also advised to get in touch with me if you want to run a server, as you will probably need help setting it up.