This effect can be beneficial. Swap the mercury for gallium and you get a neat way of producing hydrogen on demand: http://cleantech.com/news/1205/gallium-and-a

This effect can be beneficial. Swap the mercury for gallium and you get a neat way of producing hydrogen on demand: http://cleantech.com/news/1205/gallium-and-aluminum-tigers-in-your-ta http://cleantech.com/news/1205/gallium-and-aluminum-tigers-i... Too heavy for aviation but potentially useful for fuel cell vehicles.