Foxit PDF Reader
Foxit Reader is a free PDF document viewer, with incredible small size, breezing-fast launch speed and rich feature set. Foxit Reader supports Windows Me/2000/XP/2003/Vista. Its core function is compatible with PDF Standard 1.7.
In the past, you've had to download a huge PDF reader from another software company, go through a lengthy installation process and wait for an annoying splash window to disappear just to open a PDF document. Moreover, if you want to annotate a PDF document, you have to pay US$299 to buy certain software.