Riot looks nice as far as I can tell. Is there any documentation, proper list of features, what kinds of bridges exist, how to use them etc? The info on riot.im seems really sparse.
For bridges that you can run on your on "homeserver" (if you indeed want to run your own server!), see https://matrix.org/docs/projects/try-matrix-now.html#applica....
If you use the matrix.org homeserver, they bridge with a number of IRC networks, including freenode and OFTC. The closest thing to an official list that I've seen is https://github.com/matrix-org/matrix-appservice-irc/issues/2....