You will find in this page some cool Windows freewares (free software) that are of particular value to me... I use most of them daily. Those suggested softwares are, to the my knowledge, clean of any spywares or other dubious components, or they simply wouldnt figure in this list.
Open source softwares are typically free, communauty driven projects programmed and designed by computer enthusiasts, where the source code is open and freely distributed under the GPL license (which permits one to add and compile their own changes or additions and distribute it as long they also provide their own source code). You wont find draconian EULAs (user agreements required to be accepted before installing the software that can violate your consumer rights), spywares or privacy invading functions in these softwares, and you can also communicate with the developpers to report bugs or request features. You can find a good summary of the differences between the GPL and Microsoft license here. Moreover, many major open-source projects are very often cross-platform, which helps your knowledge and familiarity make the transition between different systems, if needed be. I will usually recommend them over other equivalent closed sources products, unless the project has become relatively inactive or abandonned.
For more information on the open source and open standard movement, which covers a lot more technology than windows applications, such as cross platform file format (Ogg, OpenGL, PNG, XML, SVG, etc), web server software (Apache, MySQL, PHP, MajorDomo, etc) and Linux (an entirely free and open operating system), visit gnu.org and W3C. I have also been asked where I found most of these open source softwares for Windows, try this FreshMeat.net listing, SourceForge.net category and GNUWin for a start; the rest comes with general browsing, discussion forums, etc.
Closed source freewares are traditional softwares where the source code is kept private by the creators and only the binary version is distributed (the executable after compilation). They can be the result of a single individual ambitious hobby or a company who is trying to promote a professional version of the product through a "lite" and free, but still capable, version. Some of them have minor annoyances such as ad banners, which I will mention in my description, and it will go against their ratings. I suggest a good spyware remover in any case.
Password Safe 1.7.1
Really Slick ScreenSavers