It seems the new $20 bills & Euros have a little something extra besides the pretty
colours. According to this site, they're embedded with Radio Frequency
Identification (RFID) chips that can set off those monitoring devices at
store exits designed to alert personnel that you're walking out with tagged
merchandise. The author claims that you can "fry" the RFID tag by putting
your money in the microwave - but it may explode if you do. If you don't
want your money tracked, don't think you'll avoid it by leaving the country.
A link from this site takes you to a story written way back in 2001 about
how the European Central Bank was planning to embed RFID chips in all their
Euro notes by 2005. True or not? You read it and decide.......