Some cool Vena Cava Filter images:
Gunther Tulip IVC Filter
Image by Michael @ NW Lens
Late in 2005 I was in the hospital due to injuries sustained in a motorcycle accident. A complication from that was a medical condition known as a "Saddle Embolism"… essentially a large blood clot restricting the flow of blood to my lungs. Not a good thing. To prevent further clots I had a medical filter installed in my lesser vena cava to catch them before they could get into a dangerous area.