Occasionally a freebie surprises me with a feature or two I wasn't expecting. In Bullzip PDF Printer's case it was the ability to password-protect PDF files and even watermark them. Normally, you have to fork over a fair amount of cash for these niceties. Both features--as well as the basic PDF printing--worked perfectly.
Like many free PDF apps, Bullzip is actually a front-end for the public domain Ghostscript Postscript/PDF printer driver, which is where the PDF features actually reside. Still, for anyone to take the time to implement the more advanced features in a super-clean, advertising-free little app is, well, great.
The authors accept donations, and if you're as pleased with the program as I was you might consider sending them a buck or two. They also have a pay version, PDF Writer, which according to the company is "superior to the bullzip edition in some installation related matters." You might donate by buying that program instead.
This is best of breed. Uninstall the others you may have tried and use Bullzip.