If you're looking for an Adobe Acrobat alternative to open your PDF (Portable Document Format) files, you should get Foxit Reader (98/ME/NT/2000/XP/2003; there's also a Desktop Linux version).  Now in its 2.0 version, it's extremely light and thus loads faster than Adobe Acrobat. The paid version has the following additional features:

• Rich annotation tools including Typewriter tools
• Text Viewer: Convert PDF to Text
• Annotation tool
• Editor add-on: edit PDF document
• Foxit Library add-on:manage PDF documents
• Convert other file format into PDF files
• Modify content of a PDF file ( Foxit Editor add on )