ISO-8859-15

ISO-8859-15, also known as ISO-Latin-9, is a character set that can be used for most Western European languages. It is a revision of ISO-8859-1, replacing some less common symbols with the euro sign and some other characters that were missing. According to Wikipedia, the ISO-8859-15 character set covers Basque, Catalan, Danish, Dutch (except for IJ/ij), English, Faeroese, Finnish, French, German, Icelandic, Irish, Italian, Norwegian, Portuguese, Rhaeto-Romanic, Scottish Gaelic, Spanish, and Swedish, as well as Albanian (Eastern Europe), Afrikaans, and Swahili (Africa).

LaTeX

In LaTeX, the ISO-8859-15 can be used as an input encoding with the inputenc package. The eurosym package is also needed, in order to produce the Euro symbol in the output.

\documentclass{article}
\usepackage[latin9]{inputenc}
\usepackage{eurosym}\def\texteuro{\euro}
\begin{document}
c½ur et 100\,¤
\end{document}

ConTeXt

You can use ISO-8859-15 as an input encoding via the \useregime and \enableregime commands.

\useregime[il9]
\enableregime[il9]
\starttext
c½ur et 100\,¤
\stoptext

This produces the following output (which unfortunately appears to be broken in this Wiki):