In no particular order and for no particular reason (well other than vacation contemplation).
The things that seemed to physically hurt you as a kid just really don't seem to hurt nearly as much any more. Shot in the arm? No big deal. Blood work? Ditto. Dental fillings? Bring'm on.
Things that never physically hurt before hurt now. My left foot for example. Arthritis. My foot sometimes feels like there is sand in some of the joints. Now I have to take horse pills to “lubricate” my joints. It's a pain in my...well...foot.
You realize that your parents actually were right about some things.
You begin to listen to music that your parents liked and discover that it's not all that bad. Especially given the state of popular music today.
You have to take medication to get your body to do things your body used to do all the time as a kid. Easily.
You look forward to quiet evenings instead of dreading them.
You actually take pride in the organized nature of your clothes drawers.
You move beyond the want or desire to care about the drama around you. For me, I've just learned to smile through it all.
You see just how simpler life was when you were a kid and realize just how you were lucky to be born in a previous era. Case in point: Had the Internet existed in 1976 I probably would never have left the house.
You start to see some of the little details in the world around you that, in years past, you would have just sped by.