Originally an open source, typically overengineered expert system released and supported by the Feynman Re-Creation Society in 157 a.t.. The FES was the kiss of death for both the European Union department of educational development (openly controlled by romantics since its founding) and the incredibly influential 'Morality in Education' group of fundamentalist Christians in the United States.
The FES is a compact nanoconstructed quantum computer running an emulation of the legendary physicist Dr. Richard Feynman, with apparently all of Feynman's wit and skill. Instead of teaching at one level, the FES tailored its lessons to its owners age, intelligence, emotional maturity and enthusiasm, constantly revising itself as its owner matured. It would also teach any scientific subject and would also learn of any new advancements in science and engineering.
Combining the all round excellence with its fractional cost, the FES captured a fair share of the market within 2 years of its release. It was also helped in no small part by its endorsement by the five year old superbright Vanessa Dietrich, who earned her PhD in Theoretical Physics after a year of tuition. In addition to its technical curriculum, the FES taught Art, Music (particularly the bongo drums), History, Linguistics and for still unexplained reasons Martial Arts, Lockpicking and Safecracking.
The FES was highly adaptable, and could with some patching become a general AI. This led to a proliferation of "wild" AIs, further undermining the control over AI technology held by traditional governments and megacorps, but also initiating even harsher attempts to reassert this control.
In 446, in a repeat of history, a group of Feynman's won the Nobel Prize for Physics for their theoretical work on what millennia hence would become the Conversion drive.
Currently it is estimated that 12% of all AI's are decended from, include or are/were Feynmans or cladized elements thereof, with the highest concentrations in Cyberia, Technorapture Hypernation, MPA and the Utopia Sphere.