[sandycheeks]

About ten years ago I set out to do this using a peg memory system http://en.wikipedia.org/wiki/Mnemonic_peg_system that I customized to card suits and numbers.

The best I could do was 4:25 and it was far more exhausting than I thought it would be. Trying as hard as possible three times in a day was my limit but the result was magical because I really knew the entire deck.

Instantly you can answer questions like, What is below the two of hearts? What how far is the ace of spades from the seven of diamonds? It felt surreal. I never noticed any improvement in other memory abilities as a side effect but it definitely felt like exercise of a mental sort.