Paying cash means you cannot be tracked? - think again!

[Gurm]

*shrug*

You can keep revising history all you like. Everyone knows what happened, even if you're too schizophrenic to acknowledge it.

- Gurm

[Marshmallowman]

I am really not up to date on passive tags, but years ago I was working with some dudes working on passive tags for tracking air luggage etc.

They used your usual large frame detector/scanner and the tags themselves were quite small , as everybody pointed out most of it is antennna.

I really think having notes tagged is actually possible, whether it is worth it or they actual do it is no "biggy" for me.

I think a tag that just had denomination info would be excellent stuff for money counting/verfication. And if they did serial #'s it certainly help in tracking down the big dodgy money launderers. But as every one has seen, a bit foil will block it anyway. (you could buy a tin foil wallet to go with your tin foil hat)

But microwaveing your money is just paranoid/delusional.

PS I would think all the best and latest passive tagging will be well and truly trade secrets. you are not going to find any defintive answers on just what is currently possible. Airline tagging is probably the biggy in this area for security reasons.