I recently turned 73 and one of the items on my wish list was a coloring book and gel pens. Adult Coloring Book sounds like porn but really it's not -- just a collection of fiendish mandalas and paisleys and other Indian inspired patterns.
It's an amazingly soothing and meditative activity. Once you decide what color to use, your mind wanders while you try to stay within the lines. It could be addictive . . .
Various museums have coloring pages taken from items in their collections available to download. The Smithsonian is a starting place HERE and a Google search for museum coloring pages will turn up more.
A pleasant way to relive a bit of childhood!