Nintendo DS service
Also seen in the COEX Mall in Seoul, this "Nintendo DS Service Zone":
Use power adapters (lock it while shopping), screen cleaners among other tools. This service, often provided for cell phone now extended to the NDS. Compared to Laurent's experience of asking a screwdriver in a digital camera shop (in which employees said "no we cannot do that"), this sort of little booth/area to adjust your portable console is convenient and DYI.