what does the Bible say about cremation, if anything?

Answer 1

It isn't exactly spelled out, but there is enough there for us to figure it out.
It tells us that when we die our soul leaves the earth and our body is just an empty vessel. When Jesus returns our bodies will be taken from the grave and be remade without imperfection. However to say that the body must be intact is to limit the power of God.
Rituals of burial are man made and not imposed by God. This says to me that disposal of a body is at our discretion as long as it is within the law of the land and respectful.

Answer 2

This should tell you what you need to know: