I am not talking about the eyes that Madara gave to Nagato -- the ones that are in the possesion of Obito currently (the rinnegan eyes). The eyes that Madara possessed were Izuna's eyes... not his own original eyes.
I remember when Madara met Obito, Madara has a single sharingan in his eye. Just one. Could that have been his original eye? Or did he jack that eye off another Uchiha? Seems kind of strange that he would have one eye and not two, after giving Izuna's eyes to Nagato.
Madara's original eyes have never been mentioned, but they have been seen through flashbacks. We know that he reached the Mangekyo stage with his original eyes, before he transplated Izuna's eyes into his sockets and got EMS.
So... the question stands... what do you think happened to Madara's original eyes?