Getting in gear...

I recently signed up for this really cool website called Lumosity.  It's a tool to help build memory, speed, attention, flexibility, and problem solving... and most importantly to help ward off dementia.  My great-grandmother had dementia and my uncle was recently diagnosed as well, so I'd like to do everything in my power to avoid that fate myself.  The thing I like about Lumosity is that they give you just a few exercising everyday, and track your progress.  It's actually fun!   I also play Scrabble (aka Words with Friends, Lexulous, and Wordscraper) everyday, which helps with spelling and configurations...

 
What are your favorite ways to keep your brain sharp?