This article in New Scientist discusses a plan by the US Passport Service to issue with "smart" passports carrying a digitally signed photograph by late 2004. The new passports will include a smart card that will hold a digitally signed image. Of course, a lot of people are concerned about the potential for abuse. I've never shared those concerns. I think the advantages significantly outweigh the potential problems. Utah went through a period of civic dialogue (meaning people went non-linear) a few years ago when Scott Howell introduced legislation to make the driver's license into a smart card. I thought it would be a great place to keep a digital signature, along with other information. The black helicopter crowd was out in force decrying the loss of civil liberties. The legislation was defeated. Of course, the new driver's licenses have a 2D bard code on them that holds just as much information, its just read-only.