My (and others who I infected) reaction to playing around with erlang, scheme and common lisp, was frustration. Not because these languages are bad, but because they are so nice and fun to programm with! One could even argue, that this alone results in reduced development time and better programms, but while this is definitely true, it hides the fact, that the afore mentioned languages increase efficiency of sw development also by technical means. To provide evidence for this hypothesis is out of the scope of this document, please look for yourself, there's plenty of good material about common lisp, scheme and erlang on the web, there are even life lisp coding videos on google video!
I recently bought the new erlang book. It is great and I would recommend it without hesitation.
There are also great books online that I started reading: htdp and sicp.
Oh and not to forget to mention "little schemers" of wich the chapter about the Y-combinator is online ...(yeahh nice!)
Now, all I need to do is convince my boss to start using erlang or common lisp.
There is just no point in wasting my time with java (except for j2me!).