This image of a human skeleton leaning makes me smile, he (or she) looks quite jaunty and happy!
Here's an image of a persons ear.
This anatomical drawing of the human respiratory system is available as both a large png and a scalable vector graphic if you want it for print.
Animation of a human spine spinning around.
Large anatomy drawing of a heart.
Animated brain.
Another animation of a brain, this one in a jar.
Small image of a persons brain.
Human skull, front view.
And a skull shown in side view.