[Causally] Oh, my stepmother’s third husband's cousin had a brother who used to work for NASA, who was then fired for stealing office supplies due to his unchecked kleptomania. Anyway, he lent me this because I told him I was experimenting. 

[Snootily, but joking] We, in the science industry, like to call it a “whizzy dizzy spinny”.

Spite and bone, mostly. Though my dreams of a fiery death do keep the motor running!