Arduino roll key reader

Well there is a big security flaw ith the devices we use today.... Well my consern is that I can make the device in less than 20 $ , which is way more valuable than what it can hack..

This most of thr companies knows abt this flaw but wont take action against it... I want to get to more people... Show them that they are not secure... In a way.
And it's proven that this will work.

Watch this video

Go to 3.20 and watch till end.