Car won't accelerate

So I was driving through typical friday bay area traffic when I noticed my
car failed to accelerate when I stepped on the gas pedal. No matter how far
I pressed down on the gas pedal, the vehicle failed to accelerate, nor was
there an increase in RPMs. RPMs hovered around 1200, with an
occasional spike of around 18-2000. The vehicle would slowly build up
speed to about 20-25mph.

When I finally coaxed it to a stop at the house, I turned the engine off, and
turned it back on (I'm more of a tech guy, and I figured the reboot trick of
most computers was at least a worth a try). Sure enough, everything
worked fine. Or as fine as my broken car had been running. I can't say if a
check engine light came on or not, as the CEL was on previous for a failing
throttle position sensor (has it finally gone out?) and a bad break light
switch.

So, my question is, what do you think is the issue?