You should put together one of those pictures books on shutterfly... you could fill it with pictures of you and him from birth on and maybe even create a story or just put a little bit on info under each picture. Also, you could create a book of pictures from his life and see if his wife will send you any pictures she can find?
I created a photo calendar for my dad's b-day. lol. I think he would cherish a photo book and it would help him so that he won't forget the past.