Take up Geocaching. It will take you to neat places you'd never dream of going. Even the grandkids would love it. There will probably be some hidden in your patch of woods or even in the nearby small town.
Challenge your mind a little by doing a crossword puzzle. Prepare a poster foamboard the size of the finished puzzle and get about 4 cheap Dollar Store eating trays with a lip around the edge. You can then use the trays to sort your colors and move your project from the kitchen table to the bed while eating, etc. It works well.