Here is a list of the programming languages I know
Clojure
I am currently learning this for use with Riemann.
Python
The language of choice for many projects nowadays
C++
The member events calendar for a non-profit I am a director for was written in C++; I have to fix and enhance it periodically.
Java
Quite a bit of work with Java doing Data Integration and web services.
TCL
Used in the core of the main product for an employer
Perl
Probably my favorite scripting language.
Postscript
Used to count pages in a post-payment printing system. As I already knew Forth this was fairly easy to learn as I was familiar with the paradigm.
C
Lots and lots of C, database programming, network programming.
COBOL74/85
I did not use it for over a decade after a programming class at University.
Since then I have created COBOL programs on consulting assignments at manufacturing companies, banks, insurance companies, and Wall Street trading companies. To those who only know C and the UNIX environment this is very under-rated. For batch throughput a well turned mainframe and a COBOL program can move amazing amounts of data.
Pascal
Computer Programming Class language to teach data structures.
I got re-employed the next summer to write an installer for the terminal emulator, and they decided TurboPascal was the choice.
8086 Machine Code
First paid programming position. Converting an terminal emulator written in 8080/Z80 machine code into 8086 machine code running on a PC
Z80 Machine code
Because Z80 was what the Electrical Engineering department taught students.
Fortran77
On Prime 9955 mini computers. The most successful program was a network monitoring application for X.25 networks.
Forth
My first foray into non-traditional programming languages with RPN notation
BCPL
No idea why I thought this would be fun to learn, except that it generated executable programs, which made it better than BASIC
6502 Machine Code
Acorn basic allowed you to include machine code and run it.
BASIC
Doesn’t everyone learn this at some point? they did in the 1980’s when I got my first computer (an Acorn Atom). I’ve used Acorn BASIC, Sinclair BASIC, and Apple ][ BASIC.
Algol 60/68
First language I taught myself. Used once on a Prime 9955 to help a student who turned up with a program older than myself who wanted to get it to run. The compiler generated R-mode assembler, and I let the student know they would be better off translating the concepts into FORTRAN, using a modern compiler.