The first, and easiest, method is to download a set of those oddball letters, which you can then copy and paste into any message. Here are all the characters needed for French, German, Italian and Spanish. You can highlight this list or Appendix 1, copy and paste into a text or Word file (or, if you prefer, download Appendix 1 HERE; I'll explain the appendix's accompanying numbers in the next paragraph):

FRENCH
é è à ù â ê î ô û ë ç Ç

GERMAN
ä ö ü Ä Ö Ü ß

SPANISH
á é í ó ú Á É Í Ó Ú ü ñ Ñ ¡ ¿

ITALIAN
à è ì ò ù À È Ì Ò Ù

If you want a more complete list, covering (I think) all Western European (but not Slavic) languages, copy Appendix 2 the same way, or download it HERE. Or if you want the complete list of high-level ASCII characters, including the ordinary English alphabet and mathematical and other symbols, go HERE.

Although that first method is the easiest, I rarely use it, I'm really not sure why. Somehow it seems more convenient, when I'm in the middle of a post or letter, to use the ASCII code. Here's how it's done: each character in Appendix 1 or 2 (or any of the 256 ASCII characters you find on the webpage I just gave a link to) has a number. If you hold down the ALT key and, on the numeric keypad, type 0 (zero) and that number, then release the ALT key, you get the associated character. Example: hold ALT, type 0241, release ALT...and you should have typed ñ.

Of course, you still need to consult the list to know which number to type -- I have the short list taped to the side of my computer -- but it's still somehow more satisfying than copy+paste. Remember to hold the ALT key down while you type the numbers on the numeric keypad (the keyboard numbers above QWERTYUIOP won't work).

There is a third method, but it depends on your system configuration. Many Notepad, Wordpad or Word applications have a built-in multilanguage function. If you experiment with these, holding down either CTRL or ALT or both CTRL+ALT while you type a letter (normally a vowel), it may give you a special character. Notepad on my computer in the cloister library automatically transfers " or ~ or ` or ' to the following letter, so that typing them before u, n, a or e yields, respectively, ü, ñ, à and é. Or you may have to hold ALT or CTRL+ALT while you type the signs, then release and type the letter. As I say, you'll have to experiment.

Finally: as I said above, we can't deal with exotic languages using other alphabets, like Russian, Arabic or Japanese. For these you need special software. There is one exception, Greek. I don't know Greek, but I occasionally post a known word or phrase just for fun. Eurhka! Greek letters can be posted in HTML (which works in forum and gallery posts) because there is a font for mathematical symbols, which includes the Greek alphabet. When you follow these instructions you must type < > where I have used { } (if I used < > all the instructions would be in Greek letters). So:

Type {font face = symbol}, type your Greek text here, then end the Greek by typing {/font}. The Greek letters correspond to the obvious Roman-letter equivalent, so "a" will give you a, b = b, Gg = Gg, etc.

The following are the not-so-obvious Roman equivalents:

Hh = Hh
Qq = Qq
Cc = Cc
Yy = Yy
Ww = Ww
and V = V (the final form of s).

Have fun...but gnwqi seauton!