Fire Charge

A Fire Charge is an item that was released in the 12w04 Snapshot, which you can use like flint and steel. It can be crafted with coal, gunpowder, and Blaze powder in any pattern:

When it is launched from a dispenser, it creates a fireball which acts like blaze's, catching the entity or block it touches into fire. This is pretty interesting in multiplayer PvP, since you can use this item as a cannon salvo.