Would you believe that digital signal processing as we know today was first commercially available as a component of an educational toy?

Midway through the 1970s, a group of engineers at Texas Instruments set out to design and build a chip featuring DSP technology which back then was relatively expensive and usually implemented in academia and military applications. The result was the TMS5100, TI's first speech synthesis chip, which was the centerpiece of the Speak & Spell, a wildly successful educational consumer electronics product that was years ahead of its time. Full article here.