The act of igniting one's flatulence; usually achieved by holding a lighter near the anus while passing gas. The term comes from the bluish-colored flame often resulting from methane combustion. (Note that this activity can be dangerous, and has been known to severly burn the anus and even entrails of careless practitoners.)
I have always enjoyed doing blue angels, but decided to discontinue the activity the day that a flame singed my lower intestines.
The act of igniting bowel movement.
Dumbass #1 - lets make a blue angel
Dumbass #2 - okay, here i go!!
Dumbass #1 - *lights lighter by friend's ass*
Dumbass #2 - *farts onto lighter*
Dumbass #1 is dead and dumbass #2 just lost a perfectly good pair of pants.. what a shame.