Awasu contains no advertising, spyware or nasty stuff like that.
There are two reasons why we can give away Awasu for free. The first is that the Advanced Edition and Professional Edition are [paid versions] since they offer even more features in addition to those offered by the free Personal Edition. We also get income from providing consulting services to companies using Awasu, writing plugins and customizing it for them.
The second is more altruistic. There are many, many free programs available today that have been donated to the public by their developers and each of us here at Awasu have downloaded and used many of them. Awasu is our contribution. We hope you like it.