The ISEE-3 Reboot Project is no longer able to control the trajectory of their spacecraft, but the resurrected ISEE-3 is nevertheless producing interesting scientific data. The image below (click for larger image and up-to-date feed) shows the electric field as measured by what I understand is the Scarf/Greenstadt Plasma Waves Spectrum Analyzer.
See also the latest ISEE-3 Science Status Report.
Update: see here for some explanation of the plots. The visualisation has been improved, and the data apparently shows Langmuir waves, auroral kilometric radiation, ion acoustic waves, and type III solar radio bursts. The type III bursts can be linked to solar flares.