irssi/docs/help/in/note.in

@SYNTAX:note@

NOTE is a sort of turbo-charged messaging system for irc. In short, 
it achieves at the server level what the client attempts to do with MSG 
and NOTIFY. The messaging system resembles modern voicemail systems 
(except in text); messages can be sent, stored, or set for deferred 
delivery. The client notification system works like NOTIFY, except with
greater accuracy and flexibility. 

The most common uses of NOTE are its SPY and SEND functions. SPY is similar 
to NOTIFY, except it can accept a full address to spy on, not just a nickname. 
SEND, as its name implies, sends a note to a user; if that user is not currently 
online, it will be delivered if the user logs onto irc within a set time period. 

When referring to a particular user, NOTE can deal with the standard 
nick!user@host notation. Wildcards are allowed, and any portion may be omitted, 
so long as the identifier remains unambiguous. 

Examples: 
To send a note to Joebob (whose account is jbriggs@drivein.com): 
/NOTE SEND joebob!jbriggs@drivein.com Hey there! Great movie! 

To spy on anyone from blah.com for the next 30 days: 
/NOTE SPY +30 *!*@*.blah.com A blah.com user is active 
 
This command is not available in the IRCNet. However, you've service NoteServ
available there, which allows you to do similiar things like with /NOTE command
on other IRC networks. Type /SQUERY NoteServ HELP to get more info about it.

See also: NOTIFY, SQUERY