Scala is the most enjoyable language I've ever programmed in. Most of the complexity is superficial or shaped to the problem; there are a lot of features and they can be combined to make complex things, but each of them makes sense, and there's very little in the way of fiddly edge cases to memorize.
More than I could remember all of, but certainly Python, Java, C, TCL, Javascript, C++, ML, Perl, 6502 assembler. I've stuck my head around the door of Haskell, so to speak, but not written anything substantial in it; I haven't tried Clojure (I've never heard a reason to use it over Scala, and I've become very attached to powerful type systems).
