or... n-back memory tests http://news.ycombinator.com/item?id=176264 http://news.ycombinator.com/item?id=176264 web-version: http://cognitivefun.net/test/4 ht

or... n-back memory tests http://news.ycombinator.com/item?id=176264 http://news.ycombinator.com/item?id=176264 web-version: http://cognitivefun.net/test/4 http://cognitivefun.net/test/4