I have found that it is possible to work around the "click of death", (the condition where a zip disk clicks and fails upon reading) if you have an older external zip drive (i specifically tried this with an older imac zip drive)... you can pinch the disk and it will work ... this manuver requires two people... one to pinch the zip disk, and another to back up what is on the disk.
Message
Click of death
2001-04-02 by Noah Kleiman