John Riggs just made what is probably one of the most touching tributes in memory of Satoru Iwata. He hacked Balloon Fight, replacing the protagonist with another image resembling Iwata. He also made the balloons shaped like Kirby. Riggs mentions on his video (below) that Iwata sprite was actually taken from Earthbound, another game that he was involved with.
If you want to play the game yourself, you can download the patch following the links below. The patch has to be applied to the original ROM, using tools like LunarIPS.