Fire Trap Dust

There should be a new Fire Trap dust that is crafted with redstone, gunpowder, and blaze powder.

When this dust is powered by a redstone signal it will emit a tall, thin flame going along it as far as the signal goes. It will stay on until the signal is removed. This stuff doesn't burn away so it can be reused as many times as you want.

Some ways this can be used is as a wall around your base to fend off mobs or a safer fire alternative that doesn't burn blocks around it.