There's an excellent article in Monday's New York Times about ways in which various car systems (such as navigation and anti-theft services) can be used to spy on drivers. It also includes the following:
"Tires, too, can tell on drivers. This year, Michelin began implanting match-head-sized chips in tires that can be read remotely. The company started using the chips to provide manufacturing information that could help spot failure trends and to comply with a federal law requiring close tracking of tires for recalls. But privacy activists fear that the chips, which can be loaded with a car's vehicle identification number, would allow yet another form of automated vehicle tracking. 'You basically have Web browser 'cookies' in your tires,' said Richard M. Smith, an independent privacy researcher."
What bothers me is not just that Michelin is putting 'tiny radio ID tags' (as the chips are referred to elsewhere in the article) in their tires, but that they are doing so with no notification to the consumer. I just purchased new tires for my subie, and spent some time researching various brands. I didn't notice anything about these chips on Michelin's website, and no dealer that I talked to about Michelins said anything about them.
The article can be found at:
Zack
'90 Legacy Wagon AWD Auto 155,000 miles