well i had an issue with a compact flash card.. teh program was called file recovery for compact flash, theres ones for other types of media too. and basically it scans what it can and tries to rip it. whats funny is that it also recovered pictures that was first taken from the camera which was deleted a long time ago.
on another note. NEVER EVER EVER compress anything thats of any importance. lol cause if you lose one archive, or you corrupt it... theres no way of getting back any of the data. and always have multipe backups... ive learned this the hard way and now i just leave the files as be..