The Biter, Bit

From Information Week :

Online vigilantes are taking matters into their own hands, and defacing some phishing sites to warn off the naive, a U.K. Web monitoring firm said Thursday.

According to Netcraft, a phishing site that posed as PayPal.com was recently defaced with a page created using the open-source OpenOffice application suite. The page read "WARNING -- THIS WAS A SCAM SITE" and "site killed courtesy of sickophish."

And from another article on the iNFj profile :

INFJs are champions of the oppressed and downtrodden. They often are found in the wake of an emergency, rescuing those who are in acute distress. INFJs may fantasize about getting revenge on those who victimize the defenseless. The concept of 'poetic justice' is appealing to the INFJ.

Yes, they got that right. Though not so much "revenge" as "retribution" and a not-so-subtle hint to "go thou and sin no more". Revenge as such corrodes the soul.