Paint.Net is simply amazing. When I first saw the program I knew then that the .Net framework was ready for primetime. Paint.Net has the look and feel of a professional commercial application—something that is not easy to do and requires the right tools (which is why I had been a die-hard Delphi follower).
I was a saddened to learn that the source code was pulled, but based off of this post (http://blog.getpaint.net/2009/11/06/a-new-license-for-paintnet-v35/), it does make sense. It is a shame when noble acts are abused by profiteers.
Again, kudos to Rick Brewster for this great MS Paint replacement.