However, there may be little children around, or you may be in polite company, so it's not exactly appropos.
My word, when that urge strikes, is fudge.
It substitutes easily enough, and allows the user to vent without any criticism.
Don't get me fucking wrong. There is nothing as fucking satisfying as dropping a ripe, royal fuck bomb.
But in a pinch, it'll do.
P.S. Suggestions for a "shit" substitute welcomed.