The other cool thing ddrescue does is will 'mine' away at the failing blocks by reading it from both forward and reverse and clawing out every last bit of data it can. That, coupled with the resumption capacity, logging feature and ability to specify the number of retries on bad blocks, makes it a very useful tool and I've used it to save both my drives and aquainteances' drives many times over the years.

I can't sing the praises of ddrescue enough. NB: ddrescue and dd_rescue are not the same!