Mouserider knows what he is talking about.

The technical term for this kind of camera is called a Microbolometer. They were first invented by Honeywell, but nowadays L3 markets them for the defense industry. The cheapest one I have seen so far is an OEM unit that is being sold by security suppliers. Prices are still around $5,000 for a 160x120 pixel unit.

Wait another 5 years and the prices will drop to the $1000 level. A new company is developing a non-microbolometer unit that uses tunable thin-film filters which is supposed to bring prices down to reasonable levels. I think the company's name is Redshift, or something like that.

Alex Roy bought an L3 unit and mounted it in his M5 when he beat the US transcontinental driving record earlier this year. He said it didn't help much, especially in the rain. Then again he said his average speed 92mph, so I think that anything would be a distraction at those speeds.