NeoFlash was the first dedicated DS piracy solution. It consists of a rebranded XG card sold together with a Passme clone called MagicKey. Though many people have criticized NeoFlash for being overpriced, others have praised the Magic Key for its sturdy construction
NeoFlash only works with specially encrypted roms released by Golden Sun Team, a Release Group believed to be closely associated with the company behind NeoFlash (since the members obviously had technical knowledge about NeoFlash not available to the general public.)
A patcher was released that creates encrypted roms, just like the GST releases.