Funny you said that...
Because more than one i have used OOo as a sort of quick fix for corrupted excel files. I dont know why it works but it does.
A couple of year ago a worker asked me for help in trying to recover a damaged excel file. Long story short the standard recommendations failed, then i contacted a friend who gave me the advice to try to open it with OOo and save it again. Not only did it open it without even a warning, but the data was there, untouched except for a formatting in the titles.
How can a third party open your damaged files and restore them better that the very application they were made in???