Great site!  But I didn't see some of my faves mentioned:

APL - A Programming Language
This highly symbolic and extraordinarily dense programming environment/language has operators to invert matrices, select from vectors, all kinds of great stuff for numerical methods, built right in.  The problem?  You need a special keyboard and once you write a function (program) you'll be lucky to remember what you were thinking and no one but you will ever be able to figure out what you did.  I only remember one book, by Gilman and Rose, and it was a winner.

SPITBOL - A dialect of SNOBOL developed at Illinois Institue of Technology.  Good compilation speed.  Been years since I used it but I think it may have even extended the SNOBOL spec.  If I recall the general idea here was compilation speed at (perhaps) the expense of execution speed.

PL/C - A dialect of PL/I from Cornell University designed for teaching students PL/I.  The general idea was to fix whatever you coded so that you'd have an executable, come heck or high water.  If you screwed something up, it would strip your bad syntax, put something in its place, and notify you: "PL/C uses ..."  Once you stopped laughing you saw that this was a pretty neat little compiler.

SPASM - Single Pass Assembler for use on IBM S360s and 370s, this was just a fast assembler, again for use by students.  Still, it did most of what you could want.  Nice name, and good doc support.

SuperWylbur macro language - Running under Wylbur, a monitor like Call/370, you could write pretty significant apps for system management.  Yeah, this was back in the days of MFT ( MVT was still shiny and new) and so was a 360/91 and some of us still coded programs on an IBM 029.  So Wylbur was pretty doggone nice.

Happy Coding,
J. D. Linett