Ask HN: Anybody used Mathematica, for any reason?

I was just digging around on WolframAlpha.com and there seem to be many different ways to use Mathematica:

http://www.wolfram.com/solutions/SoftwareEngineering/ http://www.wolfram.com/solutions/MedicalImaging/ http://www.wolfram.com/solutions/Chemistry/ http://www.wolfram.com/solutions/ElectricalEngineering/

I was just curious if anybody here has ever used Mathematica, and what your experience has been. I'm asking mostly because I like using Wolfram's search engine, so I am curious if other products by the company are worth looking into.