As Merlin Mann has pointed out, nerds love building Robots. It was therefore almost unfair to get the challenge of turning the K'nex system into Cyber K'nex robotic system, designed to be a more "Fun" toy to interact with than Lego Mindstorms.
I contributed to the hardware design. I then wrote, in assembly language the multi tasking software that ran on the low cost 2 processor processor that read the instruction keys and decoded the remote, played sounds, controlled the motors and flashed lights. Other people actually designed the hardware and wrote the software that was on the different models for different keys.
At one point in the development the entire team (15-20 people) were in all weekend for an end of project panic. The office resembled the scene in Blade Runner, with out of control Knex robots everywhere, and a bunch of adults who had all abandoned their families for the weekend to meet the important Christmas deadline.
It was a compelling product to work on.
Some people have even designed their own models.