I am a subscriber of Lumosity, it is a website which has a wonderful set of small games designed to improve and test memory, attention and other cognitive functions.
I have found that whenever I exercise a bit, I get a jump in my scores!!
I know this is well known, but experiencing this for myself vs just reading about it are two different things. Now that I KNOW that exercise helps, this is a nice little feedback loop for me to pull myself up these winter days and hit the Gym more often