Fuck Your Face Bitch: exactly what it says. Much more harsh than the likes of 'fuck you' or 'mother fucker' this is the ultimate fuck you right in your face bitch.
When you're angry with someone you may say 'FYFB' rather than swearing. It's an child safe acronym.
Literally, "Fuck Y'all MuthaFuckers And Suck My Dick".
Comes straight from the film, "Fear of a Black Hat" (1994), written and directed by Rusty Cundieff.
When pissed off and frustrated with friends (or just for fun dramatic effect)- especially when online, sign off a message/email/blog entry with "FYMFASMD!"