 <ul> <li><a href="http://coderay.rubychan.de/download/gem" rel="nofollow">http://coderay.rubychan.de/download/gem</a></li> <li><a href="http://softwaremaniacs.org/soft/highlight/en/" rel="nofollow">http://softwaremaniacs.org/soft/highlight/en/</a></li> <li><a href="http://code.google.com/p/syntaxhighlighter/" rel="nofollow">http://code.google.com/p/syntaxhighlighter/</a></li> </ul> <p>The second one infact does automatic language detection and works completely in the client side.</p>