To date these devices have included roll-players, pocket-sized potato cannons, clocks and color wheels designed to distinguish different kinds of potato chips.

The advantage of a potato cannon is that it fires much farther.

The disadvantage is that it takes a lot longer to reload a conventional potato cannon because you have to open it up refuel it.

This t-shirt cannon is very similar to a potato cannon, as seen in How Spud Guns Work.

Notice that the motion that comes out of an internal combustion engine is rotational, while the motion produced by a potato cannon is linear (straight line).

A potato cannon can move a 2" diameter potato projectile over 100 yards at a speed of 40 mph.

A air powered potato cannon is much stronger than a combustion cannon.

You can see in the figure that a device called a piston replaces the potato in the potato cannon.

This is a classic HowStuffWorks article that describes the construction and operation of the traditional potato cannon:

The traditional potato cannon is a combustion device - it uses hairspray as its fuel and the spark unit from an outdoor grill to ignite it.