MIT students create and circulate open source, covert RFID rings to subvert campus tracking system

A reader writes, "A couple years ago MIT changed their dorm security/student tracking
policy. They hired security contractors to work in dorms and required
everyone to tap their RFID cards upon entry (no vouching for
friends/guests). Most students complied. Some moved out. Some got in
trouble ;)"

"Fast forward to this week. There was a student-run 'ring delivery'
event on campus where roughly 100 students received programmable RFID
capable devices. Most of these were rings that could be mistaken for
class rings. Students also received documentation on 125 kHz RFID
systems, how to make inexpensive reader/writer devices, and how to
produce more rings.

"I've attached a copy of this documentation for your viewing pleasure.
Additional digital resources for the project can be found at I think it is likely that new
students will run this event again."