The BBC reports on a promising new method for storing CO2, tested by researchers in Iceland. From the article:
The researchers report an experiment in Iceland where they have pumped CO2 and water underground into volcanic rock.
Reactions with the minerals in the deep basalts convert the carbon dioxide to a stable, immobile chalky solid.
Even more encouraging, the team writes in Science magazine, is the speed at which this process occurs: on the order of months.