What to get the father?

Okay, my father is the hardest one to shop for, and yes, I haven’t finished my Christmas gift shopping yet! =\.

My father seems to have enough clothing, and likes stuff that is useful.

I know everyone is different, and everyone likes different things, but what did you get your father? And what should I get my father? He already has a nice wallet, and winter gear… He has a watch too, it feels like he has everything.

I realized that blindly shopping and hoping to find something does not work in this case, so are there any suggestions?