SylWord counts syllables in words, outputting a tab-separated list of words and their classifications. It does this by counting tokens according to a language-specific rule file, which consist of regex rules for identification of vowels, dipthongs, tripthongs etc.
SylWord is written in Java, and is compatible with JVM 1.4.2 and up. To make it useful you'll need to write your own syllable rules, though this isn't too difficult in practice.
Download SylWord-0.1b.tar.gz.
Simply run the SylWord class to run the tool. Extra information on editing and updating syllable pattern files is in the README, and the javadoc is here (yes it's really simple).