Disk of Returning

The Disk of Returning was an item sold for a mere 10 gp by NPCs. In early runescape, banned people got sent to the blackhole. It was an area of nothingness. Banned people were forced to serve their time in this place. People could visit the people in the black hole using the disk of returning. The problem was, if you drop the disk while you are in the black hole, you can't escape. The banned person can then pick up the Disk of Returning and escape from the depths of this Black Hole. This caused innocent black hole visiters to be scammed into dropping it. Jagex then removed the black hole and made an alternate form of banning in which the player can't log on. They now sell for 8-10 million which is a huge jump from that 10gp they used to be sold for.