[avmich]

This is all false for APL. First, APL is right there in the history with Fortran and Lisp - and its "every ten years" became irrelevant already when it was used to analyze IBM 360 hardware and found some bugs which were fixed in time for shipping. Second, these languages are truly for very wide ranges of problems - it's the industry curse that APL isn't used more widely; I guess the reason is it's harder to learn. But you can do can use it for really everything. Who'd thing JavaScript would be the language to write Linux emulator? So it's less wonder that k is used for OS writing.