My current interests in XMPP leaded me to ejabberd (XMPP server) and this to some XEPs PubSub and POSH, and this to wondering about using XMPP as a queue system. Then I discovered some discussions comparing AMQP vs XMPP and realized that both RabbitMQ (an implementation of AMQP) and ejabberd were programmed in Erlang. I was astonished that three of the currently most interesting projects were implemented in the same language (if we include couchDB).
This is why I decided to read "Programming Erlang". I've nearly read half of the book and my expectations has been really exceeded:
As missing parts (not sure if they are cover at the end of the book), I found out the following:
To sum up, really a MUST READ if you are curious about other programming languages apart from Java, Python or Ruby.