It's a physical reaction that a person has when they get over stimulated or excited when typing, often when someone is in the act of Instant Messaging. It causes the typer to make several mistakes and become flustered, eventually just feeling exhausted and unable to continue typing.
Someone who is addicted to obtaining money and building wealth. A money addict and fanatic. Breadheads often work more than one full-time job, and some even participate in illicit activities to "obtain the bread".