No one language can keep me happy for a long time. So my happiness language changes every year.
GTD - Python (Also my happiness language)
Bread and butter - Java (although that might change too given the recent developments)
GTD - Python (Also my happiness language)
Bread and butter - Java (although that might change too given the recent developments)
I find my "bread and butter" and Getting things done" languages are both Perl.
[1] Now I've got Arduino driven lasers-on-servos, I need to implement face recognition on live video next...