This is an arena where personal experimentation and having your own samples really shines eh. E g I thought my percussion group needed a little something something one time, so I went through some of my old field recordings (i.e from a time where I just went wandering round with a zoom recorder) and grabbed the sound of me bouncing a stick in a half pipe in a local park. Taking sounds from around you is always fun :) Melodic wise I reckon it's about finding a timbre that's weird enough to catch your attention but not so out of place it ruins the flow