I don't think the right alt key works "out of the box" --you'd have to
modify it to be a Compose key. You could also make the right ctrl key
to be Compose, or the right Microsoft key, if your k/b has one. In
Linux, there's usually a command somewhere that will make a compose
key; in Windows, you can download a freebie called "AllChars" which
does the almost same thing. (The key will still work as Ctrl for other
functions.)
The way it works: You momentarily hit Compose, then fairly quickly in
succession you hit the letter you want to modify and something that
looks like the mark you want to modify it with. (The order of the
letter and the mark doesn't matter.) You can get all the usual
European diacritical marks, plus the €, the ¥ the £, the ¢, the
German ß, and ½, ⅓, ¼, °, Greek ų and probably a few things I
forgot. The ß and the ° are made by striking the desired key twice
after Compose. The fractions by Compose 1 2, and so on.
The compose key will work for virtually any test, including the
console, email, LO, whatever you have.
--doug