I just came across a link to a Ruby version of the web book “Data Structures and Algorithms” which looks very promising. However, what is even better is that the author, Bruno Preis, has written the same book in 8 different languages: C++, Java, C#, Python, Ruby, Lua, Perl, and PHP.
Sure, for the CF readers here he is leaving you out - but it is pretty easy to translate PHP code into equivilant CF code; plus you can always just use the Java if you want. Hopefully some of you find this educational and, better yet, interesting!