AMD has formally announced they are introducing enhanced virus protection security technology embedded in all AMD64 processors which in combination with Microsoft's Data Execution Prevention in the upcoming Windows XP SP2 will help to render some viruses, specifically buffer overrun exploits, inoperable and prevent them from replicating and spreading to other systems.

On a semi-related note, Bill Gates has 'predicted' the death of the password as a security measure.

Oh great, now we're gonna have to take a data ID card with us... as if it will help! Come on! Who thinks that hackers wont hack/recreate that! It's not practical, but it can be done!

I'd like to see retinal ID scans...kind of hard to hack that - unless someone takes your eyeball from you...

Retinal scans. They didn't help much in Demolition Man or Minority Report

Well AMD64's virus protection doesn't require any external devices / scanning systems.