These aren't funny, but I'm writing in a genre where swearing is generally discouraged, but I can't have Satan saying "dang it" so I've had to get creative. Most of the time in dialogue, you can actually get it across without the terms at all. But when I've needed to:
"Blast!" works really well for an exclamation
"Oh for crying out loud!" fills the mouth well and has a very nice rhythm
When I was told to give up swearing, I couldn't even think substitutions or I'd slip back into using the words out loud. Sad, really.