A FOIL (F-Off I'm Leaving) E-Mail is a short e-mail you send to all your co-workers to tell them you have to ditch work for the day, for reasons you are not going to disclose but are most likely related to sunny weather, holiday shopping, or a hangover.
Elements of a "FOIL E-Mail" are described below:
Hello all, (#1, greet everyone cheerfully).
I 'gotta roll. (#2, state your intentions with confidence.)
A personal emergency has occurred, important. (#3, vague excuse that sounds important.)
Joe "Tequila" <= (#4, friendly signature with nickname)
"I did not have implants, I just had a growth spurt."
"Britney Spears" (#5 - cheesy quotation under your signature to create distraction.)