Cenocell

Cenocell is a great development in the use of SCMs (supplementary cementitious materials) to the effect of changing the S from "supplementary" to completely "substitutionary." Many currently used ready mixes already contain a good portion of ash or slag (both considered 100& post-industral recycled), but what is so spectacular about this Cenocell is not only is it 100% SCM, but that it doesn't require aggregates, which are the primary source of compressive strength in typical mixes (I'm sure they would still use steel reinforcement for tensile strength). 7000psi is definitely a high strength mix (although certain large applications require much higher).
The price ($50/yd) actually isn't that outrageous, and I'm sure it will come down after time, but the only catch is it needs to be heated to cure. That means all members have to either be precast when brought to site, or there must be some sort of large oven machine on site. Keep in mind the need to 'bake' it increases the embodied energy (however it's quite possible the net embodied energy is less).
Only other concern would be in regard to leachate, since fly ash contains metals that could leach hazardous materials if coming into contact with acids.
Regardless, this could be really big, the fact that there is a 'renewable resource' that is so light and strong by itself. Thanks Doyoyo (cool name, too).