Irssi's colors that you can use in text formats, hilights, etc. :

                           text            text            background
   ---------------------------------------------------------------------
   %k      %K      %0      black           dark grey       black
   %r      %R      %1      red             bold red        red
   %g      %G      %2      green           bold green      green
   %y      %Y      %3      yellow          bold yellow     yellow
   %b      %B      %4      blue            bold blue       blue
   %m      %M      %5      magenta         bold magenta    magenta
   %p      %P              magenta (think: purple)
   %c      %C      %6      cyan            bold cyan       cyan
   %w      %W      %7      white           bold white      white
   %n      %N              Changes the color to "default color", removing
                           all other coloring and formatting. %N is always
			   the terminal's default color. %n is usually too,
			   except in themes it changes to "previous color",
			   ie. hello = "%Rhello%n" and "%G{hello} world"
			   would print hello in red, and %n would turn back
			   into %G making world green.
   %F                      Blinking on/off (think: flash)
   %U                      Underline on/off
   %8                      Reverse on/off
   %9      %_              Bold on/off
   %I                      Italic on/off
   %:                      Insert newline
   %|                      Marks the indentation position
   %#                      Monospace font on/off (useful with lists and GUI)
   %%                      A single %
   %XAB            %xAB    Color from extended plane (A=1-7, B=0-Z)
   %ZAABBCC    %zAABBCC    HTML color (in hex notation)

 In .theme files %n works a bit differently. See default.theme
 for more information.


 MIRC colors that you can use when writing text to channel:

               foreground (fg)     background (bg)
   -------------------------------------------------------
    0          white               light gray   + blinking fg
    1          black               black
    2          blue                blue
    3          green               green
    4          light red           red          + blinking fg
    5          red                 red
    6          magenta (purple)    magenta
    7          orange              orange
    8          yellow              orange       + blinking fg
    9          light green         green        + blinking fg
    10         cyan                cyan         
    11         light cyan          cyan         + blinking fg
    12         light blue          blue         + blinking fg
    13         light magenta       magenta      + blinking fg
    14         gray                black        + blinking fg 
    15         light gray          light gray

 These colors may differ depending on your terminal. In particular
 the meaning for background may be the same as for the foreground
 (bright colors, no blinking), and orange often looks like brown or
 dark yellow.

 How to use these colors ('#' means a number as MIRC color code):
 
 <Ctrl>-b        set bold
 <Ctrl>-c#[,#]   set foreground and optionally background color
 <Ctrl>-o        reset all formats to plain text
 <Ctrl>-v        set inverted color mode
 <Ctrl>-_        set underline
 <Ctrl>-7        same as <Ctrl>-_
 
 To reset a mode set it again, f.e.
   <Ctrl-C>3<Ctrl-V>FOO<Ctrl-V>BAR
 creates black on green FOO followed by a green on black BAR