Quote from brucemitchell
Anyway, maybe slime balls could be crafted into Magma Cream with a bucket of lava or something?
They are crafted into magma cream, with blaze powder. It's been like that for several updates already.
Also, in regard to your ideas of more slimeball uses, I think they should be placeable on the tops of blocks, and makes those blocks sticky (Stops items, slows down/stops players and mobs, etc). I think that would be a cool idea.