Mathematica is one of my favorite tools. I first learned about it (version 2–it is now version 8) as an undergraduate at Georgia Tech. I learned how to use it in the computer labs, but I wanted to use it in my dorm room. Unfortunately, I was reminded about the necessity of a floating-point unit to using complex calculating software at a speed faster than a sliderule; my Apple Powerbook 145B was woefully underpowered, lacking the necessary FPU that would have made Mathematica fly. As it was, I plotted one curve and it took 45 minutes to complete the operation. It was shortly after that that I upgraded to a Power Macintosh 8500, which significantly sped things along.
Mathematica was originally built by an exquisitely smart fellow named Steven Wolfram. I had the pleasure of meeting him at Georgia Tech when he come for a visit and lecture–I believe talking about his work thus far on what become his book A New Kind of Science and the upcoming release of Mathematica 3. Even though I probably didn’t say anything of substance or intelligence when I met him, he was still very polite and cordial to me.
Apparently, Mathematica’s development paralleled Steve Job’s work on the NeXT computer and then his return to Apple. Wolfram has some nice things to say about Jobs and his influence on Mathematica in the Guardian here.