Sagging breasts are so relevant.... -_-
I've heard that high sodium intakes cause the puffiness below your eyes. Obviously sodium has many ill effects on your body, so decreasing your intake will benefit more than just puffy eyes! Stress and sleep imbalances can also be culprits.
Keep some spoons in your freezer. In the morning, hold them below your eyes, and this can help the puffiness.
Also, I used to put a bit of Blistex (Lip Medex) below my eyes which seemed to help a little, if you can stand the tearing / burning sensation :)
I've also heard hemorrhoid cream can tighten up the bags, although I can't speak from experience....
There are also many creams you can buy for a pretty hefty price.
Still, sometimes puffy baggy eyes are genetic and there's not much you can do about it.