I keep some bookmarks of file manipulation with Python, please update if you know more. Thank you!

Documents / Office:

pyExcelerator: Generating Excel97 files
OOoPy: Manipulating OpenOffice documents
dbfpy: Manipulating dBase, Foxpro DBF files
vobject: Reading vCard & vCalendar
PalmDB: manipulating PalmPDB & PRC

Multimedia:

PyMedia: Manipulating wav, ogg, avi, divx, dvd etc..

Photos / Images:

TheBigPicture: manipulating EXIF & IPTC metadata in JPEG & TIFF files
jpeg.py: manipulating EXIF metadata of JPEG

GPS:

PyGarmin: Manipulating data from Garmin GPS

Utilities:

PyUNRAR: unpacking RAR files
libextractor: extract data from any type of files