Interactive C, or IC, is a variation of the C programming language. From the README:
IC is a C compiler/interpreter for use with 6811 boards. It is
designed to be easy and fun to use -- just type C expressions in and
they are run immediately. (The underlying implementation compiles on
the fly to a fairly effient pseudocode interpreter).
In addition to interactivity, IC is multitasking, and has drivers for
a wide variety of I/O sources, including motors, various analog
sensors, servos, infrared in and out, a simple beeper, and LCD screen.
Libraries for IC are currently available for the MIT Rev 2.21 robot
controller board, or for the Rug Warrior from Mobile Robots:
Inspiration to Implementation by Joe Jones and Anita Flynn (a great book!).
IC was developed by Randy Sargent and Fred Martin of the MIT Media Laboratory for an MIT undergraduate design course. Though there is also a commercial version, free source and binaries are available for PC's, Mac's, and UNIX machines at ftp://chelona.media.mit.edu/pub/projects/interactive-c.