Being able to bend over and touch my toes...without bending my knees.
Being able to do a cartwheel on the front lawn without hurting myself.
Being able to swim 2500 yards in an hour and 10 minutes...without wishing I hadn't the next day.
Being able to do P90X without throwing up.
Throwing water balloons with my kids while jumping on the trampoline, with the hose running full tilt.
Being able to watch back-to-back movies without getting bored.
Playing a video game on my iPhone every now and then.
Eating potato chips ON my sandwiches, just to have that bit of crunch in every bite.
Enjoying silly candy like Nerds Ropes without feeling guilty.
Kicking a soccer ball to with the neighbor kid...and being able to keep up with him.
Throwing paper airplanes with my kids.
Shaving my head completely bald because I want to, not because I have to. (But that's starting to be a bit of stretch
)