In between fierce rounds of Mario Kart DS at Seattle s Chop House, Nintendo's Perrin Kaplan came over to our table and had a seat. After asking what we were most impressed with from the summit (Brain Flex), she wanted to know how to market a game like that (a portable IQ test, more or less). How do you market a game to adults, when the DS in America still chiefly appeals to youth? Should Brain Flex ads appear in Good Housekeeping? Kaplan herself said she didn t plan to buy time on MTV for the game - she s right, the hardcore know about it already and will pick up the brain teasing title and its sibling Brain Training. So, readers, how do you reach an older set for these two games? Send lockbox DS kits to retirement homes? Send those same kits to corporate America and hope to pique their interest?