Look at this graph of U.S. execution methods since 1776

From here, and kind of nuts: as you can see below, there are essentially five methods by which the United States has ever killed someone (in an execution sense, at least):

• Hanging

• Firing Squad

• Electrocution

• Gas Chamber

• Lethal Injection

Regardless of where you lie on the "We should execute people" continuum, you can probably argue that hanging, firing squad, …