jargon.artrocity.com
New Hacker's Dictionary the Jargon File v 4.4.6
[Usenet; common] Acronym for ‘Friend Of A Friend’. The source of an unverified, possibly untrue story. This term was not originated by hackers (it is used in Jan Brunvand's books on urban folklore), but is much better recognized on Usenet and elsewhere than in mainstream English.