About five years ago we did a major renovation to our house and the architect suggested we use spray foam for insulation. There were many benefits; it was a green technology, it provided a vapor barrier, it added some rigidity to the structure, it filled every nook and it could get wet without growing mold. The down side: In those days a truck showed up at your house with 55 gallon drums of chemicals and a very loud machine used to mix the foam and to power the sprayers. They did a great job, they were pros, but I was not about to call them for my newest project, a small basement room makeover.
Step in "Foam it Green" from sprayfoamdirect.com, which has a DIY version of the big truck. For $330 I got two small canisters connected to hoses which meet and mix at a spray gun. The kit also came with extra nozzles, safety equipment (gloves, glasses etc) and instructions. Note: It's important to read these even though it is against every guy's better judgement. With things like temperature of the foam and spray force, you don't want to waste the product or the applicators.
The process went well and after a minute of spraying I got pretty good at it. (You can see the finished product in this picture.) After the foam cured -- about four minutes -- I added a second layer, where needed. The best part: I've insulated the whole room and I'm not itching! Next up: Drywall.