Language features: it depends on what you need. I am a huge fan of Lisp (started using professionally in 1982) and to a lessor degree Smalltalk (I wrote a nift

Language features: it depends on what you need. I am a huge fan of Lisp (started using professionally in 1982) and to a lessor degree Smalltalk (I wrote a nifty little NLP library for Pharo). That said, sometimes I really like the strict typing of Haskell, which I am using right now to develop a commercial product. Smalltalk, especially with the increasing good modern Pharo system, is a great platform for some application, especially for getting close to data and flexibility in trying UI ideas. In any case, Alan Kay has always been an inspiration to me.