My new passport has what appears to be DNA-strings across the ID-part, only visible under UV (or my blu-ray)
Then across there are 3 wavy lines saying "DENMARK DANISH PASSPORT". I am surprised at how cool it actually looks.
Also, every single paper page in the passport has threads of flourscent material in it - at first I thought it was just a couple of hairs lighting up (they are about the length of eyelashes), but there are about 30 on every single page and they light up blue, red, green and yellow. Very nice!
My bank card says "M C"
My healthcare card does not appear to have anything hidden anywhere..