I don't run irssi on my desktop, so no. Alerts are provided in the form of rcirc-track-minor-mode. No, there is no sound, but it's Emacs, so just implement it.
The deeper issue is, what are you doing at work that can't be done inside Emacs? You don't need sound if you are already in Emacs!
Oh, I hadn't heard of rcirc, I didn't realize you were using IRC via Emacs already (I hold no allegiance to ERC). I'll check it out.
One more question: have you noticed bitlbee failing to proxy lines with non-ascii characters? That was by far the most annoying thing I ran into, but I was using it via Xchat --- for example, a non-technical friend copy/pasted some text with curly quotes and I get nothing but "FriendName: " (blank line). I had to return to Pidgin just because of that.
