ZNC is an IRC bouncer that is very helpful in the sense that it will allow you to connect many clients to one IRC server and only appear as one.
It works somewhat like this:
ZNC connects, no clients need be running on other machines, and will autoconnect if the connectiong between it and the IRC server is lost for any reason.
ZNC has some useful features such as it’s own ignore list (negating the need for per-client ignore list), as well as auto-away which sets an away flag and changes the active nick to an alternative one once the last client disconnects.
It also supports various other addons, one I use is called znc-push (the bouncer sees it as simply “push”), this allows your nick or whatever string you specify to pushed to a notification service on your mobile device, unfortunately it has the potential to be abused by those that want to wind you up, but the author thought about this with a nick blacklist option, which works much like an ignore, a similar push addon exists for Colloquy but is not as flexible.