They'd be given to a friend of mine so he could go to a swingers' club, in the orgy room, and while they're all busy he'd throw my ashes on them while yelling "surprise motherfuckers !"
I'd get myself turned into a tree, and then maybe when the tree is tall enough someone could chop it down and turn it into a book used as a album with old photos of me and stuff in it. Then all the people that read it would literally be holding my life in their hands. That'd be nice.
Anyway, in all seriousness I'm gonna get scattered on my own land. There's an Oak tree in one of my fields, my dad wants to go under there, so does my mum and so will I. The estate will remain in family hands I should think so maybe one day my kids will end up there as well.
Divided up into dime bags and secretly dispersed into the water mains of cities around the world. Once consumed, my ghost will compel the victims to shitpost themselves into an early grave.
i would ask someone to keep them safe, and then when theres a family reunion for the first year of my death,they are to mix it into the coffee and make my family drink it so i can prank them even when im in hell.
(i would also be absorved and passed along my descendants,isnt that meta?)
Diamonds, space etc. But I really like the idea of the urban legend where my family think that my ashes are actually a rare spice and gradually eat them without realising it. Partially because I like fucking with them, but also because I've this bizarre respect for those tribes who eat their relatives as part of their funeral rites. You're their flesh and blood both living and dead. Obviously respect does not equal going through with active cannibalism, but a symbolic act like consuming ashes is kind of... I dunno. Not entirely foul.