"This is crap. Real all-terrain wheelchairs have tank treads."
This was Autoblog reader Shiznannigan's reaction to the Superfourin chair posted earlier. He then graciously referred us to the Tank Chair.
The Tank Chair (TC) is a one-person vehicle that uses tracks (like a tank) instead of standard wheels. While the inventor doesn't give much in the way of technical specs, the TC has reportedly been tested in snow, mud and sand. Each chair is custom-built to customer's specifications-- a 300-pound person with a T1 spinal break would have an altogether different chair (including suspension characteristics)--than someone who is, say, a 150-pound paraplegic.
Pictures, video, and additional information can be found at the link.