All types share type object as their parent. Or maybe I should say all types are of type object. Unless you need to store any of the standard datatypes, you can simply make the value of the node an object, and then cast it back when retrieving/using it.
If you do need to store values that are comprised of only a standard data type, you can either wrap them in your own custom type and then store them, or you could use byte pointers.
If you do need to store values that are comprised of only a standard data type, you can either wrap them in your own custom type and then store them, or you could use byte pointers.