I agree - many free PDF viewers and readers are out there. Linux has many, and even on Windows alone, there are alternatives to "A-Bloat-Be" Software (such as Foxit PDF Reader, much faster and cleaner than Acrobat with less bloat).
Also, many open-source programs can create and edit PDFs, such as PDFCreator - a virtual printer - and OpenOffice can also put a document into a PDF.
Edit: Regarding file compression, I prefer 7zip, the format is very nice, free, and the free utility to make them also packs/unpacks almost anything (including .zip, .rar, and numerous others).