LAS VEGAS -- There are tons of healthcare products at CES this year, including all sorts of gadgets for monitoring your heart and activity levels and uploading them to Web services.

The most far-out one I've seen so far is an electronic prosthetic foot and ankle shown by SpringActive, a Tempe, Ariz.-based startup.

Using federal grants, the company is developing an ankle replacement system with "robotic tendons" that use sensors, springs and microprocessors to mimic the foot's natural springing motion.

The idea is to restore the natural gait to amputees. The company is still developing the system and needs FDA approval, but it believes it can start selling the devices later this year. They'll likely cost well over $10,000 apiece but their actuators are designed to operate for a minimum of five years.

To demonstrate, they strapped a sensor onto my leg and I swung it back and forth. The demo unit flexed up and down as if I was taking big steps. The company said the system tracks the wearer's motion 1,000 times per second to keep the ankle in sync, and it weighs less than 4 pounds.

The company also is building an exoskeleton based on similar technology. The system -- called Rolle, or Robotic-Lightweight Load Carrying Exoskeleton -- is intended to help soldiers carry heavy loads on their backs. (Maybe it caught my eye because I'm lugging a big laptop bag around the show.)

Rolle's "jackspring" system dynamically adjusts to the weight and walking conditions. It mounts on backpacks and specially equipped boots.