On the way to UBICOMP 2004 I had the pleasure of going through customs in Canada. It turns out that Canadian customs will speed you through the horrendously long customs lines if you are willing to be biometrically identified by iris scan. You can only qualify for the program if you are considered a low customs risk. The details of the program are here

It isn't clear to me why this is useful technology. Is it really reasonable to classify someone as a low-customs risk? The current (non-biometric) system relies on random checks and customs officials noticing someone is acting nervous. Now, if you've never been caught smuggling before you can sign up for the program and smuggle stuff much more easily without all the trouble and stress of dealing with a customs officer. On the other hand, if it's a system to track the movement of people (which they don't admit), then it will be much more accurate and efficient at recognizing when people have crossed the border. But even that doesn't make a lot of sense because there are much better ways of tracking people without them knowing it. for example, looking at there cell-phone tower and credit cards records.

I was nearly deported for taking this picture by the way.