One of the more interesting ones is this:
Alfio Bonanno and Christophe Cornubert have created a 1 ton cube of CO2. At 27-foot it's not inconsiderable.
Going on figures from the Guardian, each person in the UK, on average, produces nearly 10 of these each year. That's a lot of carbon, and yet it's nothing compared to places that the US, who produce twice as much per capita.