Homescreen Designer makes it easy to create attractive, original themes for Windows Mobile Smartphones. The program lets you add your own background image, select which 'plugin' elements appear on your Home screen (e.g. email, calendar, network info etc), and even change system notification windows. The home screens we created in the trial version of the software were of high quality and weren't watermarked by the program at all.
The only real problem with the program is that it uses an unconventional design which makes its interface quite ugly and fairly hard to work with. I never understand why software developers feel the need to come up with non-standard window borders, menu bars and so on when the default options are already very easy to use. The program also lacks a help system, though the 'readme.htm' file does include a basic manual.
Homescreen Designer is a good choice if you're interested in customising your phone. It's only let down by its design which renders it less intuitive than it might have been.