Make sure to get the Cryo'd cement! Don't just settle for the straight audio grade, as has been suggested! You'll just have to upgrade later on and that stuff is not easy to resell here on Audiogon if it ain't Cryo'd.
Seriously, if you haven't handled cement powder before be aware that it's not the most pleasant stuff to handle. If you decide to try it wear gloves and long sleaves or you will find it will suck all the moisture from any skin it comes in contact with and your hands will be as pleasant to touch as a sun-dried dead fish for the next few days. Also definitely wear a dust mask and work outdoors. As has been said, the powder is very fine and gets everywhere, and some of the ingredients can wreak havoc in your lungs.
Seriously, if you haven't handled cement powder before be aware that it's not the most pleasant stuff to handle. If you decide to try it wear gloves and long sleaves or you will find it will suck all the moisture from any skin it comes in contact with and your hands will be as pleasant to touch as a sun-dried dead fish for the next few days. Also definitely wear a dust mask and work outdoors. As has been said, the powder is very fine and gets everywhere, and some of the ingredients can wreak havoc in your lungs.