In celebration of the forthcoming Pokemon Emerald.
In classic Nintendo fashion, a special limited edition green Game Boy Advance SP will be released alongside the release of Pokèmon Emerald. This limited edition SP is a dark green color and features a silhouette of the Pokèmon Rayquaza on its cover.
This Green SP will be available for the price of 12,500 Yen ($115), the same as a regular GBA SP, but it will only be available through Nintendo's Japanese Pokèmon Centers (and their website). The system won't be available until September, but the website will be taking pre-orders starting August 16th. Below is a picture of the unit.