All classics. May I suggest some less obvious and more creative ones as well? How about diaper-fucking, especially in really wet and messy Pampers? Like, in the
legs-up missionary position or a 69? Perhaps you would like to incorporate bouncers, pacifier gags or other babyish-themed bondage? Oh, and we can't forget to include baby oil massages. Or a messing contest, in which everyone takes a dose of laxative and then they all mess, and whoever 'wins' is whoever has the messiest diaper by weight.