Peter Kämpf (Peter.Kaempf@fbmev.de)
Starting with Fortran, I discovered Tcl as a frontend several years ago and love to program with it. I work on a complex GUI for some number-crunching applications and needed to develop all sorts of code to improve data entry and display. Samples are:

Splines with free (non-monotonic) values of X and Y

Listboxes which can be sorted by drag-and-drop

Utility to transfer files and folders between different encodings

Ah, the last one gave it away: Yes, I prefer to code on the Mac.