I picked up this poster a couple years ago, and I must admit I've neglected it a bit. However I've finally got the wall space for it in my new office (it's A0), so it's going up. I love the simplicity of the graphics and the simple but shocking comparisons such as Tea v Coffee.

Designed by Timm Kekeritz in 2007 and based on the study by Hoeckstra et al. in their study Water Footprint of Nations. It uses one of my favourite font families of all time; Thesis by Luc(as) de Groot of http://www.lucasfonts.com/. Specifically it uses TheSans and TheSerif.

The great irony of the poster is that paper is the most water intensive item on it.

Here's a little bit on the theory:

[excerpt from waterfootprint.org]
Virtual water content: The virtual-water content of a product (a commodity, good or service) is the volume of freshwater used to produce the product, measured at the place where the product was actually produced (production-site definition). It refers to the sum of the water use in the various steps of the production chain. The virtual-water content of a product can also be defined as the volume of water that would have been required to produce the product at the place where the product is consumed (consumption-site definition). We recommend to use the production-site definition and to mention it explicitly when the consumption-site definition is used. The adjective ‘virtual’ refers to the fact that most of the water used to produce a product is not contained in the product. The real-water content of products is generally negligible if compared to the virtual-water content.

It's good to see that the idea has been taken further, see more here: http://virtualwater.eu/

More about them and their design agency is http://raureif.net/