Plugin for displaying code snippets in WordPress
A really comfortable and easy to use plugin for displaying code snippets in WordPress posts is called SyntaxHighlighter Evolved. You can find more information here http://www.viper007bond.com/wordpress-plugins/syntaxhighlighter/
After installing and activating it, just enclose your code snippet in [] and [/], depending on the language you are using.
Example:
<?php echo 'Hello world!'; ?>
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