Free online conversion service.
Possible to determine unknown file format too.
Thats a pretty catchy selling point in itself—you can convert PDFs to Excel files, huge TIFF images to PDF, icon files into images, and the site even does a little OCR work on certain image-to-text conversions.
Convert from PDF:
(some conversion support OCR conversion for scanned PDF)
PDF to: Open Office Writer, Open Office Calc, Open Office Impress, MS Word, MS Excel, HTML, text
PDF to image: BMP, JPG, GIF, PNG, TIF
PDF to AutoCAD (dwg / dxf)
Convert from XPS: to Open Office Writer, Calc, Impress formats; to image BMP, JPG, GIF, PNG, TIF; to text, HTML, MS Word/Exsel. More Info »
Other File Conversions: Excel to CSV, XML to LINT, HTML to RSS, ASC TO PDB / EBC, MAC to UNIX to DOS
CSV to DELIM to FIX
SORT FILE, PDF INFO, COMPARE FILES, MP3 INFO, FILEINFO, ICONV