NOTICE <nick|channel> :message

NOTICE will send a notice message to the
user or channel specified.

NOTICE supports the following prefixes for sending
messages to specific clients in a channel:

@ - channel operators only
+ - channel operators and voiced users

Two other targets are permitted:

$$servermask - Send a message to a server or set of
               servers
$#hostmask   - Send a message to users matching the
               hostmask specified.

These two require Oper Priv: oper:mass_notice

The nick can be extended to fit into the following
syntax:

username@servername

This syntax is used to securely send a message to a
network service.
