Gift Help

Hello everyone,

My Grandfather-in-law has been losing his hearing but recently it seems even more so. His birthday is coming up and we would like to find him a special gift that he and my Grandmother-in-law can use together. Something they can use to interact in a way that creates communication, something fun but also something cerebral-oriented as he is a very intelligent man. It would be really nice for them to do something aside from watching tv and connect. Any ideas? Thank you so much in advance.