What are the risks of a Van Der Graaf?

When turned on a Van de Graaff generator collects a static charge on its surface. When someone or something that is positively or negatively charged touch the surface a shock can be felt due to the transfer of electrons from the generator to the object or person. This shock is relatively weak and harmless because there is a definite amount of electrons that can collect on the dome of the generator. However, if a capacitor that allows the buildup of charge is brought near it the voltage of the shock can be increased. An example of this would be a leyden jar which allows the charge to collect and give a greater "shock" than the surface area of the generator. If a large container was made into a leyden jar such as a 5 gallon bucket it would have a much more powerful discharge that could be fatal.