With the CF Sprayer you can place/spray Construction Foam.
It'll spray 13 blocks of CF, on a flat layer mostly in the following shape:
Can be crafted multiple times, shapless recipe.
Each pellet loaded in allows two uses of the sprayer. Usage of CFPack allow you to skip manual refilling and hold up to 129 pellets ready.
If using a CF Sprayer to spray on a Scaffold it will replace the Scaffold with construction foam. So you can use a scaffolds in combination with Construction Foam to create walls (etc.) without the need to break unnecessary, left-over construction foam.
The scaffolds are dropped if replaced by construction foam.
As of 1.70, CF will cover and harden around placed cables, allowing one to hide ugly wiring with pretty CF walls. Note that this will not otherwise affect the effect of sprayed CF.