According to In fact, 15,000¥ is also the trade-in value for a PSP Value Pack and a slim-line Silver PS2. The original DS models aren't far below that mark, still worth 14,000¥ (about $125).
[Update: redirected to Cheap Ass Gamer's April 4th post, from where this information was lifted over a month and a half later. CAG's CheapyD writes us with some more current information: "Currently, my guess is that the trade-in values of the DS Lite and Xbox 360 are about even. Right before E3, I was actually able to buy a new DS Lite at that very store for 16,800¥ (MSRP)."]

