Currently spending time and effort in learning Scala.
I'm really interested in this language as apparently they were able to port some functionality in the java world, where people are used with stiff code, and get surprised by the fact that syntactic sugar exists.
Overall it seems a good language, even if they probably put so much syntactic sugar that it's somewhat difficult to understand code if you freshly started. And the lack of good quality documentation makes this harder!
There are official tutorials on scala-lang.org,
but they are not exactly well written. Just to give an example, let's take
the case classes
page. Everything nice, but someone should tell java programmers about
comprehensive matches, which are available in Scala via the sealed
keyword.
With special consideration for what I believe is the target audience (i.e. Java people) I believe someone should write a Learn You Some X for Great Good guide here!
My good colleague Altug linked me this list, which contains some Scala too. I think I've seen it popping out of Hacker News. Or was it Stack Overflow? Anyway, in there I could find this one, which might be of interest, given my recent effort with Perl.