Sometimes I've seen mentioned an Oracle DUL (data unloader) tool, to be used for situations like yours. However, DUL seems to be an internal Oracle tool: you'll have to call Oracle support and ask to have somebody sent to your place to recover the database, and it can be very expensive.
You could also try http://sourceforge.net/projects/jdul/, although the project doesn't seem to have any release now.
All the best, take it as a lesson in backup and recovery you'll never forget.