How do you format moans?

[aLittleCrow]

The title pretty much says it all - how exactly do you indicate that a character you control is currently moaning (hopefully out of pleasure)? I know that one can use italics or colours or other fonts to indicate this, but I'm asking specifically about the written word, all other formatting options discarded. And if you use moaning sound effects, please do share them, since I can only find about ten on Yahoo answers.

[Sunstone]

Interesting question! Hmm... well, for me generally if I'm describing a character moaning in an RP I usually just do it subtly, like "A-ah~" or "Mm~". Or I'll just describe the action and say something like "*a faint moan escaped from her lips*". 

[Buio Banned]

It really rather depends on the kind of moan that is being given. Moans encompass such a wide variety of vocalizations that the exact format I use will frequently depend on the exact reaction I am describing. I'll usually employ one of or a mixture of the three first options given up above, and almost always combine indirect descriptions (she couldn't quite hold back the soft moan that purred from deep within her throat as the stimulation made her toes curl) with direct descriptions in dialogue "M~Mnhh~ Ah, yes; just like that~"

The tilde is of course an astoundingly useful punctuation mark to give the dialogue that melodic quality that tends to come with sexual arousal or seductive speech.