See http://www.cl.cam.ac.uk/~mgk25/unicode.html
(has a "Where do I find ISO 10646-1 X11 fonts?" section.)

See also http://www.gentoo.org/doc/en/utf-8.xml

See also http://www.bbsinc.com/iso8859.html,
which lists ASCI ISO 8859-1 (Latin-1) with HTML names

   Ø
   ε
   &vepsilon;

 * Files and strings which contain only 7-bit ASCII (0x00 to 0x7F)
   have the same character encoding under both ASCII and UTF-8

 * No ASCII byte (0x00 to 0x7F) can appear as part of any other character.

 * The first byte of a multi-byte sequence that represents a non-ASCII
   character is alwas in the range 0xC0 to 0xFD and it indicates
   how many bytes follow for this char.  All further bytes are in the
   range 0x80 to 0xBF.  This allows easy transitions and means its
   robust against missing bytes.

 * All possible 2**32 UCS cods can be represented.
 
For web files, the encoding is specified up the headers, e.g.

 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

and more basically, that the default Apache serves up utf-8 by default
for html adnd text, i.e.

   AddType text/html;charset=UTF-8 html  
   AddType text/plain;charset=UTF-8 txt
 
(This is now wikipedia's default, for example.)

"Emacs has quite good basic utf-8 starting from version 21.3"

---------------------------------------------------------

In my XEmacs on cs (21.4.15 on Jan 2006),
under "View - Mulitlingual - Describe current coding systems", it says

  Coding system for saving this buffer:
  u -- utf-8
  Default coding system (for new files):
  u -- utf-8
 Coding system for keyboard input:
  u -- utf-8
  Coding system for terminal output:
  u -- utf-8

 M-X set-input-method
 M-X toggle-input-method

 One online usenet comment says
 M-X set-keyboard-coding-system RET utf-8 RET
 "will fix [utf8 input] in 21.5 but unfortunately is still broken in 21.4"

---------
 EmacsForMacOS wiki
http://www.emacswiki.org/cgi-bin/wiki/EmacsForMacOS

The OS X Terminal.app uses UTF-8 by default. 
To get the correct behaviour from the Emacs that comes with OS X, 
I use the following settings in my .emacs file:
  (set-terminal-coding-system 'utf-8)
  (set-keyboard-coding-system 'utf-8)
  (prefer-coding-system 'utf-8)
This also works with XEmacs 21.5.9 and above, at least.

If you want to input chars that your keyboard doesn't have,
you need an "Input Method".
Choose one using 'M-X set-input-method'.
Toggle in on and off using 'C-\'.

To describe input methods, use C-h I
 (global-set-key kbd "C-X C-m i") 'set-input-method)
 (prefer-coding-system 'utf-8)

Another way is to use C-q
By default, if you type C-q followed by some digits, 
they're intepreted as octal code.
Or 
 (setq read-quoted-char-radis to 10)
Then
 C-q 160 ret
and you get a space.
Move back one and use 'C-u C-x =' and get something like
 character:  ...
 charset:    ...
 code point: ...
 syntax    :  which means: whitespace

Input methods:
 latin-1-postfix (Quail)
  a" is ä 
  s/ is ß 
  c, is ç  
  a' is á 
  o/ is ø
  O/ is Ø   

control-h s to see syntax table

M-x list-input-methods to see a brief description of each.
 latin-1-postfix or latin-1-alt-postfix  (for accents and umlauds)
 greek
 greek-jis         (?)

 latin-2 : central and eastern europe
 latin-3 : albania, gaeilc, german,
 

See http://www.bjlug.org/activities/emacs.html

xemacs:
(insert-ucs-character CODEPOINT)
 Documentation:
 Insert character which is converted from give UCS codepoint.
 Can I type it in hex? 
 Directions say ... To type it in hex, type eg ?\x4EEE
 ... but I haven't seen that work.

 From what see, I need to type the number in base 10

 (string-to-number "ffff" 16)
  => 65535