If you really want some serious rattler rattles or rattler anything else, get yourself to Waynoka, Oklahoma the weekend after Easter for the annual Rattlesnake Roundup. You cannot imagine all the things you can do with a rattlesnake--dead or alive. I've seen fiddlers fiddlin' with rattles in, over, under, around, through, and everywhich way including loose, and attached to anything and everything you never thought possible. (how's that for total incorrect grammerocityness?!)
But rattles in the fiddles are for sissies. If you want to have a really good time, try fiddlin' with a LIVE rattler INSIDE your fiddle. Then, if you should live through that, maybe you could let your imagination go wilder than a fiddlin' rattlesnake dancer, and win some prizes for everything you never wanted to do with a rattlesnake and were terrified but drunk enough to do anyway.