Jamboree on the Air, or JOTA
An annual Scouting event that uses amateur radio (HAM Radio) to link Scouts around the world, around the nation and in your own community. Held on the third full weekend of October each year, this worldwide jamboree requires no travel, other than to a nearby radio amatuer's HAM shack. Many times the HAM's will come to you by setting up at a Scout camporee, or perhaps they already have a HAM shack at your council's camp.
For more information on JOTA, download the flyer here