i bought a nintendo ds and the dr. kawashima brain training game a few weeks ago for my sister in law, and i am very very impressed with this toy. it is easy yet challenging and undoubtedly helpful in keeping your mind sharp and agile. it is a good family thing as we all do it and it has become quite competitive with top scores and brain ages etc.
personally i feel a lot more switched on in general and the memory results speak for themselves, when i started i could only remember 8 of the 30 words (apparently people can only remember 8 things) but now its in the mid 20's because it taught me to remember images instead of words. i always hated maths and thought sudoku was rubbish (because i couldn't do it) but now i'm plowing my way through the sets and having a great time.
they are about $200 new (get them to throw in a case / headphone set) and the game is $40 - $50, or $70 for an older model second hand. i highly recommend this for you or your kids or whoever to improve your most important asset, your mind.
anyone else playing with one of these?