[auto]
"whois [group]" lists users of a group.
"any [group]: [message]" pings a single member of the group, one who is in the room if possible.
"[group]: [message]" pings all members of the group currently in the room, or if none are present, does nothing.
"all [group]: [message]" pings all members of the group, period.
"groups" gives a list of pingable sites (not including some aliases which are also recognized).
Pings can optionally be followed by a colon and a message.