Get rid of all that hidden tracking and collaboration data nice and easily with this MS released tool...

http://www.microsoft.com/downloads/details.aspx?FamilyID=144e54ed-d43e-42ca-bc7b-5446d34e5360&displaylang=en
(only works with XP/02)

Story on what can happen if you keep this information on the file...

http://www.theregister.co.uk/content/4/35277.html