[CodeMage]

It may sound trite, but it's true: it all depends on how you define "happy". I'm happy coding in Java, C#, C++, Python and ActionScript 3, to name a few. I was happy to code in Lisp and plain old vanilla C, too. My happiness with programming doesn't depend entirely on the language. I can honestly say that going back to more "mainstream" languages after coding in Lisp has made me even happier, because I had new ways of doing stuff that wouldn't have occurred to me before.

I often run into stuff I can't do in one language that I could do in another. The challenge this poses can be (and often is) frustrating, but it can also be fun: how can I do XYZ as expressively and elegantly as possible in language ABC?

It's the kind of work I do that makes me happy or unhappy, and the freedom I have in it.