We demonstrate extreme ionospheric response to the large interplanetary electric fields during the Halloween storms that occurred on October 29 and 30, 2003. Within a few (2--5) hours of the time when the enhanced interplanetary electric field impinged on the magnetopause, dayside total electron content increases of ~40% and ~250% are observed for the October 29 and 30 events, respectively. During the Oct 30 event, ~900% increases in electron content above the CHAMP satellite (~400 km altitude) were observed at mid-latitudes (¿30 degrees geomagnetic). The geomagnetic storm-time phenomenon of prompt penetration electric fields is a possible contributing cause of these electron content increases, producing dayside ionospheric uplift combined with equatorial plasma diffusion along magnetic field lines to higher latitudes, creating a daytime super-fountain effect.