Handmade [[xref:http://video.syfy.com/shows/ghosthunters/steves_gear_guide/#////shows/ghosthunters/steves_gear_guide/ion-generator/v124130|ion generators|Ion Generator : Steve’s Gear Guide]] charge the air with negative ions, supposedly to provide spirits with enough energy to properly manifest, move objects, or communicate. Ghost hunters report sudden changes of energy during a haunting, which is how these tools came into play. [[xref:http://www.assap.org/newsite/htmlfiles/NID.html|Measuring ion levels can be difficult|www.assap.org]] and inaccurate, as ion concentrations tend to vary over short distances, especially indoors. And, of course, connecting a spike in ion levels to a spiritual presence is a leap of the imagination.
Image: Courtesy of [[xref:http://www.hobbytron.com/product1260.html|Hobbytron.com|Hobbytron.com]]